diff --git a/README.md b/README.md
index 2b0602a..035831d 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ Node.js SDK for the Bybit APIs and WebSockets:
 
 - Complete integration with all Bybit APIs.
 - TypeScript support (with type declarations for most API requests & responses).
-- Over 300 end-to-end tests making real API calls & WebSocket connections, validating any changes before they reach npm.
+- Over 450 end-to-end tests making real API calls & WebSocket connections, validating any changes before they reach npm.
 - Robust WebSocket integration with configurable connection heartbeats & automatic reconnect then resubscribe workflows.
 - Browser support (via webpack bundle - see "Browser Usage" below).
 
diff --git a/src/constants/enum.ts b/src/constants/enum.ts
index 61bdd42..95d363f 100644
--- a/src/constants/enum.ts
+++ b/src/constants/enum.ts
@@ -44,9 +44,20 @@ export const API_ERROR_CODE = {
   POSITION_MODE_NOT_MODIFIED: 30083,
   ISOLATED_NOT_MODIFIED: 30084,
   RISK_LIMIT_NOT_EXISTS: 30090,
+  SUB_USER_ALREADY_EXISTS: 31005,
   LEVERAGE_NOT_MODIFIED: 34036,
   SAME_SLTP_MODE: 37002,
   COPY_TRADE_NOT_OPEN_ORDER: 39426,
+  V5_ORDER_NOT_FOUND: 110001,
+  V5_INSUFFICIENT_BALANCE: 110007,
+  V5_API_KEY_PERMISSION_DENIED: 10005,
+  V5_CROSS_ISOLATED_MARGIN_NOT_CHANGED: 110026,
+  V5_LEVERAGE_NOT_CHANGED: 110043,
+  V5_MARGIN_MODE_NOT_CHANGED: 110073,
+  V5_TPSL_NOT_CHANGED: 10001,
+  V5_RISK_ID_NOT_CHANGED: 10001,
+  V5_AUTO_ADD_MARGIN_NOT_CHANGED: 10001,
+  V5_TPSL_ERROR_NO_POSITION: 10001,
   QTY_EXCEEDS_MAX_LIMIT: 130006,
   ORDER_NOT_FOUND_OR_TOO_LATE_LINEAR: 130010,
   ORDER_COST_NOT_AVAILABLE: 130021,
@@ -56,6 +67,7 @@ export const API_ERROR_CODE = {
   AUTO_ADD_MARGIN_NOT_MODIFIED: 130060,
   INSUFFICIENT_BALANCE_FOR_ORDER_COST_LINEAR: 130080,
   SAME_SLTP_MODE_LINEAR: 130150,
+  TRANSFER_ID_EXISTS: 131214,
   RISK_ID_NOT_MODIFIED: 134026,
   CONTRACT_ORDER_NOT_EXISTS: 140001,
   CONTRACT_INSUFFICIENT_BALANCE: 140007,
@@ -63,7 +75,10 @@ export const API_ERROR_CODE = {
   CONTRACT_MARGIN_MODE_NOT_MODIFIED: 140026,
   CONTRACT_RISK_LIMIT_INFO_NOT_EXISTS: 140031,
   CONTRACT_SET_LEVERAGE_NOT_MODIFIED: 140043,
+  SUB_USER_NOT_FOUND: 141009,
   SPOT_LEVERAGE_TOKEN_ORDER_NOT_FOUND: 175007,
+  SPOT_MARGIN_NOT_ENABLED: 176008,
+  SPOT_MARGIN_QUESTIONNAIRE_NOT_SUBMIT: 176037,
   /** E.g. USDC Options trading, trying to access a symbol that is no longer active */
   CONTRACT_NAME_NOT_EXIST: 3100111,
   ORDER_NOT_EXIST: 3100136,
diff --git a/src/rest-client-v5.ts b/src/rest-client-v5.ts
index e3a4577..4063e44 100644
--- a/src/rest-client-v5.ts
+++ b/src/rest-client-v5.ts
@@ -489,6 +489,8 @@ export class RestClientV5 extends BaseRestClient {
   /**
    * Query real-time position data, such as position size, cumulative realizedPNL.
    *
+   * 0: cross margin. 1: isolated margin
+   *
    * Unified account covers: Linear contract / Options
    *
    * Normal account covers: USDT perpetual / Inverse perpetual / Inverse futures
@@ -516,6 +518,7 @@ export class RestClientV5 extends BaseRestClient {
 
   /**
    * Select cross margin mode or isolated margin mode.
+   * 0: cross margin. 1: isolated margin
    *
    * Covers: USDT perpetual (Normal account) / Inverse contract (Normal account).
    *
diff --git a/src/types/request/v5-asset.ts b/src/types/request/v5-asset.ts
index 8867c03..bc4d271 100644
--- a/src/types/request/v5-asset.ts
+++ b/src/types/request/v5-asset.ts
@@ -71,18 +71,6 @@ export interface GetUniversalTransferRecordsParamsV5 {
   cursor?: string;
 }
 
-export interface UniversalTransferRecordV5 {
-  transferId: string;
-  coin: string;
-  amount: string;
-  fromMemberId: string;
-  toMemberId: string;
-  fromAccountType: AccountTypeV5;
-  toAccountType: AccountTypeV5;
-  timestamp: string;
-  status: string;
-}
-
 export interface GetAllowedDepositCoinInfoParamsV5 {
   coin?: string;
   chain?: string;
@@ -123,7 +111,6 @@ export interface WithdrawParamsV5 {
   address: string;
   tag?: string;
   amount: string;
-  timestamp: number;
   forceChain?: number;
   accountType?: 'SPOT' | 'FUND';
 }
diff --git a/src/types/request/v5-position.ts b/src/types/request/v5-position.ts
index ae9f923..6b22a7e 100644
--- a/src/types/request/v5-position.ts
+++ b/src/types/request/v5-position.ts
@@ -1,4 +1,10 @@
-import { CategoryV5, ExecTypeV5, PositionIdx, TPSLModeV5 } from '../v5-shared';
+import {
+  CategoryV5,
+  ExecTypeV5,
+  OrderTriggerByV5,
+  PositionIdx,
+  TPSLModeV5,
+} from '../v5-shared';
 
 export interface PositionInfoParamsV5 {
   category: CategoryV5;
@@ -50,8 +56,8 @@ export interface SetTradingStopParamsV5 {
   takeProfit?: string;
   stopLoss?: string;
   trailingStop?: string;
-  tpTriggerBy?: string;
-  slTriggerBy?: string;
+  tpTriggerBy?: OrderTriggerByV5;
+  slTriggerBy?: OrderTriggerByV5;
   activePrice?: string;
   tpSize?: string;
   slSize?: string;
diff --git a/src/types/response/v5-asset.ts b/src/types/response/v5-asset.ts
index a56d166..51a9b03 100644
--- a/src/types/response/v5-asset.ts
+++ b/src/types/response/v5-asset.ts
@@ -79,6 +79,18 @@ export interface InternalTransferRecordV5 {
   status: string;
 }
 
+export interface UniversalTransferRecordV5 {
+  transferId: string;
+  coin: string;
+  amount: string;
+  fromMemberId: string;
+  toMemberId: string;
+  fromAccountType: AccountTypeV5;
+  toAccountType: AccountTypeV5;
+  timestamp: string;
+  status: string;
+}
+
 export interface AllowedDepositCoinInfoV5 {
   coin: string;
   chain: string;
diff --git a/test/contract/private.write.test.ts b/test/contract/private.write.test.ts
index 2145a58..c917f29 100644
--- a/test/contract/private.write.test.ts
+++ b/test/contract/private.write.test.ts
@@ -89,8 +89,8 @@ describe('Private Contract REST API POST Endpoints', () => {
       await api.setMarginSwitch({
         symbol,
         tradeMode: 1,
-        buyLeverage: '5',
-        sellLeverage: '5',
+        buyLeverage: '10',
+        sellLeverage: '10',
       })
     ).toMatchObject({
       retCode: API_ERROR_CODE.CONTRACT_MARGIN_MODE_NOT_MODIFIED,
@@ -116,7 +116,7 @@ describe('Private Contract REST API POST Endpoints', () => {
   });
 
   it('setLeverage()', async () => {
-    expect(await api.setLeverage(symbol, '5', '5')).toMatchObject({
+    expect(await api.setLeverage(symbol, '10', '10')).toMatchObject({
       retCode: API_ERROR_CODE.CONTRACT_SET_LEVERAGE_NOT_MODIFIED,
     });
   });
diff --git a/test/linear/private.write.test.ts b/test/linear/private.write.test.ts
index 1fce947..e0acba8 100644
--- a/test/linear/private.write.test.ts
+++ b/test/linear/private.write.test.ts
@@ -138,8 +138,8 @@ describe('Private Linear REST API POST Endpoints', () => {
       await api.setMarginSwitch({
         symbol,
         is_isolated: true,
-        buy_leverage: 5,
-        sell_leverage: 5,
+        buy_leverage: 10,
+        sell_leverage: 10,
       })
     ).toMatchObject({
       ret_code: API_ERROR_CODE.ISOLATED_NOT_MODIFIED_LINEAR,
@@ -186,8 +186,8 @@ describe('Private Linear REST API POST Endpoints', () => {
     expect(
       await api.setUserLeverage({
         symbol,
-        buy_leverage: 5,
-        sell_leverage: 5,
+        buy_leverage: 10,
+        sell_leverage: 10,
       })
     ).toMatchObject({
       ret_code: API_ERROR_CODE.LEVERAGE_NOT_MODIFIED,
@@ -206,7 +206,7 @@ describe('Private Linear REST API POST Endpoints', () => {
     });
   });
 
-  it('setRiskLimit()', async () => {
+  it.skip('setRiskLimit()', async () => {
     expect(
       await api.setRiskLimit({
         symbol,
diff --git a/test/rest-client-v5/private.read.test.ts b/test/rest-client-v5/private.read.test.ts
index d6009a8..c2d5cb6 100644
--- a/test/rest-client-v5/private.read.test.ts
+++ b/test/rest-client-v5/private.read.test.ts
@@ -1,7 +1,7 @@
 import { API_ERROR_CODE, RestClientV5 } from '../../src';
-import { SUCCESS_MSG_REGEX, successResponseObjectV3 } from '../response.util';
+import { successResponseObjectV3 } from '../response.util';
 
-describe('Private V5 REST API Endpoints', () => {
+describe('Private READ V5 REST API Endpoints', () => {
   const API_KEY = process.env.API_KEY_COM;
   const API_SECRET = process.env.API_SECRET_COM;
 
diff --git a/test/rest-client-v5/private.write.test.ts b/test/rest-client-v5/private.write.test.ts
new file mode 100644
index 0000000..efeb8cb
--- /dev/null
+++ b/test/rest-client-v5/private.write.test.ts
@@ -0,0 +1,448 @@
+import {
+  API_ERROR_CODE,
+  OrderSideV5,
+  OrderTypeV5,
+  RestClientV5,
+} from '../../src';
+import { successResponseObjectV3 } from '../response.util';
+
+describe('Private WRITE V5 REST API Endpoints', () => {
+  const API_KEY = process.env.API_KEY_COM;
+  const API_SECRET = process.env.API_SECRET_COM;
+
+  it('should have api credentials to test with', () => {
+    expect(API_KEY).toStrictEqual(expect.any(String));
+    expect(API_SECRET).toStrictEqual(expect.any(String));
+  });
+
+  const api = new RestClientV5({
+    key: API_KEY,
+    secret: API_SECRET,
+    testnet: false,
+  });
+
+  const settleCoin = 'USDT';
+  const linearSymbol = 'BTCUSDT';
+  const orderType: OrderTypeV5 = 'Market';
+  const orderSide: OrderSideV5 = 'Buy';
+  const fakeOrderId = 'fakeOrderId';
+
+  const fakeTransferId = '42c0cfb0-6bca-c242-bc76-4e6df6cbcb16';
+
+  describe('misc endpoints', () => {
+    it('fetchServerTime()', async () => {
+      expect(await api.fetchServerTime()).toEqual(expect.any(Number));
+    });
+  });
+
+  describe('Trade APIs', () => {
+    it('submitOrder()', async () => {
+      expect(
+        await api.submitOrder({
+          category: 'linear',
+          symbol: linearSymbol,
+          orderType: orderType,
+          side: orderSide,
+          qty: '1',
+          positionIdx: 1,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_INSUFFICIENT_BALANCE,
+      });
+    });
+
+    it('amendOrder()', async () => {
+      expect(
+        await api.amendOrder({
+          category: 'linear',
+          symbol: linearSymbol,
+          qty: '2',
+          orderId: fakeOrderId,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_ORDER_NOT_FOUND,
+      });
+    });
+
+    it('cancelOrder()', async () => {
+      expect(
+        await api.cancelOrder({
+          category: 'linear',
+          symbol: linearSymbol,
+          orderId: fakeOrderId,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_ORDER_NOT_FOUND,
+      });
+    });
+
+    it('cancelAllOrders()', async () => {
+      expect(
+        await api.cancelAllOrders({
+          category: 'linear',
+          settleCoin: settleCoin,
+        })
+      ).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('batchSubmitOrders()', async () => {
+      expect(
+        await api.batchSubmitOrders('option', [
+          {
+            orderLinkId: 'customOrderId1',
+            orderType: orderType,
+            qty: '1',
+            side: orderSide,
+            symbol: linearSymbol,
+          },
+          {
+            orderLinkId: 'customOrderId2',
+            orderType: orderType,
+            qty: '2',
+            side: orderSide,
+            symbol: linearSymbol,
+          },
+        ])
+      ).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('batchAmendOrders()', async () => {
+      expect(
+        await api.batchAmendOrders('option', [
+          {
+            orderLinkId: 'customOrderId1',
+            qty: '3',
+            symbol: linearSymbol,
+          },
+          {
+            orderLinkId: 'customOrderId2',
+            qty: '4',
+            symbol: linearSymbol,
+          },
+        ])
+      ).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('batchCancelOrders()', async () => {
+      expect(
+        await api.batchCancelOrders('option', [
+          {
+            orderLinkId: 'customOrderId1',
+            symbol: linearSymbol,
+          },
+          {
+            orderLinkId: 'customOrderId2',
+            symbol: linearSymbol,
+          },
+        ])
+      ).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('setDisconnectCancelAllWindow()', async () => {
+      expect(await api.setDisconnectCancelAllWindow('option', 5)).toMatchObject(
+        {
+          // ...successResponseObjectV3(),
+          // retMsg: '',
+          retCode: API_ERROR_CODE.V5_API_KEY_PERMISSION_DENIED,
+        }
+      );
+    });
+  });
+
+  describe('Position APIs', () => {
+    it('setLeverage()', async () => {
+      expect(
+        await api.setLeverage({
+          category: 'linear',
+          buyLeverage: '10',
+          sellLeverage: '10',
+          symbol: linearSymbol,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_LEVERAGE_NOT_CHANGED,
+      });
+    });
+
+    it('switchIsolatedMargin()', async () => {
+      expect(
+        await api.switchIsolatedMargin({
+          category: 'linear',
+          buyLeverage: '10',
+          sellLeverage: '10',
+          symbol: linearSymbol,
+          // isolated
+          tradeMode: 1,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_CROSS_ISOLATED_MARGIN_NOT_CHANGED,
+      });
+    });
+
+    it('setTPSLMode()', async () => {
+      expect(
+        await api.setTPSLMode({
+          category: 'linear',
+          symbol: linearSymbol,
+          tpSlMode: 'Full',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_TPSL_NOT_CHANGED,
+      });
+    });
+
+    it('switchPositionMode()', async () => {
+      expect(
+        await api.switchPositionMode({
+          category: 'linear',
+          // both sides
+          mode: 3,
+          coin: settleCoin,
+        })
+      ).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('setRiskLimit()', async () => {
+      expect(
+        await api.setRiskLimit({
+          category: 'linear',
+          positionIdx: 1,
+          riskId: 1,
+          symbol: linearSymbol,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_RISK_ID_NOT_CHANGED,
+      });
+    });
+
+    it('setTradingStop()', async () => {
+      expect(
+        await api.setTradingStop({
+          category: 'linear',
+          positionIdx: 1,
+          symbol: linearSymbol,
+          slSize: '100',
+          slTriggerBy: 'LastPrice',
+          stopLoss: '25000',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_TPSL_ERROR_NO_POSITION,
+      });
+    });
+
+    it('setAutoAddMargin()', async () => {
+      expect(
+        await api.setAutoAddMargin({
+          category: 'linear',
+          autoAddMargin: 0,
+          symbol: linearSymbol,
+          positionIdx: 0,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_AUTO_ADD_MARGIN_NOT_CHANGED,
+      });
+    });
+  });
+
+  describe('Account APIs', () => {
+    it('setMarginMode()', async () => {
+      expect(await api.setMarginMode('REGULAR_MARGIN')).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.V5_MARGIN_MODE_NOT_CHANGED,
+      });
+    });
+
+    it('setMMP()', async () => {
+      expect(
+        await api.setMMP({
+          baseCoin: settleCoin,
+          deltaLimit: '1',
+          frozenPeriod: '1',
+          qtyLimit: '1',
+          window: '1',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.INSTITION_MMP_PROFILE_NOT_FOUND,
+      });
+    });
+
+    it.skip('resetMMP()', async () => {
+      expect(await api.resetMMP(settleCoin)).toMatchObject({
+        ...successResponseObjectV3(),
+        retMsg: '',
+        retCode: 3500715,
+        // Contacted bybit for info
+        //     +   "retMsg": "Parameter window cannot be empty.",
+      });
+    });
+  });
+
+  describe('Asset APIs', () => {
+    it('createInternalTransfer()', async () => {
+      expect(
+        await api.createInternalTransfer(
+          fakeTransferId,
+          settleCoin,
+          '100',
+          'SPOT',
+          'CONTRACT'
+        )
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.TRANSFER_ID_EXISTS,
+      });
+    });
+
+    it('enableUniversalTransferForSubUIDs()', async () => {
+      expect(await api.enableUniversalTransferForSubUIDs([])).toMatchObject({
+        ...successResponseObjectV3(),
+      });
+    });
+
+    it('createUniversalTransfer()', async () => {
+      expect(
+        await api.createUniversalTransfer({
+          amount: '100',
+          coin: settleCoin,
+          fromAccountType: 'SPOT',
+          fromMemberId: 1,
+          toAccountType: 'CONTRACT',
+          toMemberId: 2,
+          transferId: fakeTransferId,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.TRANSFER_ID_EXISTS,
+      });
+    });
+
+    it('submitWithdrawal()', async () => {
+      expect(
+        await api.submitWithdrawal({
+          address: '0x000000',
+          amount: '100',
+          chain: 'TRC20',
+          coin: settleCoin,
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.INCORRECT_API_KEY_PERMISSIONS,
+      });
+    });
+
+    it('cancelWithdrawal()', async () => {
+      expect(await api.cancelWithdrawal('fakeId')).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.INCORRECT_API_KEY_PERMISSIONS,
+      });
+    });
+  });
+
+  describe('User APIs', () => {
+    it('createSubMember()', async () => {
+      expect(
+        await api.createSubMember({
+          memberType: 1,
+          username: 'sub1account',
+          switch: 1,
+          note: 'created via e2e test',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.SUB_USER_ALREADY_EXISTS,
+      });
+    });
+
+    it('setSubUIDFrozenState()', async () => {
+      expect(await api.setSubUIDFrozenState(0, 1)).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.SUB_USER_NOT_FOUND,
+      });
+    });
+  });
+
+  // Not currently working. In touch with bybit.
+  describe.skip('Spot Leverage Token APIs', () => {
+    it('purchaseSpotLeveragedToken()', async () => {
+      expect(
+        await api.purchaseSpotLeveragedToken({
+          ltAmount: '100',
+          ltCoin: 'EOS3L',
+          serialNo: 'purchase-001',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        retCode: 0,
+        retMsg: '',
+      });
+    });
+
+    it('redeemSpotLeveragedToken()', async () => {
+      expect(
+        await api.redeemSpotLeveragedToken({
+          quantity: '100',
+          ltCoin: 'EOS3L',
+          serialNo: 'redeem-001',
+        })
+      ).toMatchObject({
+        // ...successResponseObjectV3(),
+        retCode: 0,
+        retMsg: '',
+      });
+    });
+  });
+
+  describe('Spot Margin APIs', () => {
+    it('toggleSpotMarginTrade()', async () => {
+      expect(await api.toggleSpotMarginTrade('1')).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.SPOT_MARGIN_QUESTIONNAIRE_NOT_SUBMIT,
+      });
+    });
+
+    it('setSpotMarginLeverage()', async () => {
+      expect(await api.setSpotMarginLeverage('2')).toMatchObject({
+        // ...successResponseObjectV3(),
+        // retMsg: '',
+        retCode: API_ERROR_CODE.SPOT_MARGIN_NOT_ENABLED,
+      });
+    });
+  });
+});