diff --git a/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/SmartWallet.cs b/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/SmartWallet.cs
index 42220ec5..47f3e001 100644
--- a/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/SmartWallet.cs
+++ b/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/SmartWallet.cs
@@ -124,7 +124,6 @@ internal async Task<RpcResponseMessage> Request(RpcRequestMessage requestMessage
         private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage requestMessage)
         {
             // Deserialize the transaction input from the request message
-            Debug.Log("Creating UserOp...");
 
             var paramList = JsonConvert.DeserializeObject<List<object>>(JsonConvert.SerializeObject(requestMessage.RawParameters));
             var transactionInput = JsonConvert.DeserializeObject<TransactionInput>(JsonConvert.SerializeObject(paramList[0]));
@@ -146,7 +145,6 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
             var executeInput = executeFn.CreateTransactionInput(Accounts[0]);
 
             // Create the user operation and its safe (hexified) version
-            Debug.Log("Create the user operation and its safe (hexified) version...");
 
             var partialUserOp = new EntryPointContract.UserOperation()
             {
@@ -155,43 +153,26 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
                 InitCode = initData.initCode,
                 CallData = executeInput.Data.HexStringToByteArray(),
                 CallGasLimit = transactionInput.Gas.Value,
-                VerificationGasLimit = 150000 + initData.gas,
-                PreVerificationGas = 50000,
-                MaxFeePerGas = latestBlock.BaseFeePerGas.Value + 2,
-                MaxPriorityFeePerGas = 2,
+                VerificationGasLimit = 100000 + initData.gas,
+                PreVerificationGas = 21000,
+                MaxFeePerGas = latestBlock.BaseFeePerGas.Value * 2 + BigInteger.Parse("1500000000"),
+                MaxPriorityFeePerGas = BigInteger.Parse("1500000000"),
                 PaymasterAndData = Constants.DUMMY_PAYMASTER_AND_DATA_HEX.HexStringToByteArray(),
                 Signature = dummySig,
             };
+            partialUserOp.PreVerificationGas = partialUserOp.CalcPreVerificationGas();
             var partialUserOpHexified = partialUserOp.EncodeUserOperation();
 
             // Update paymaster data if any
-            Debug.Log("Update paymaster data if any...");
 
             partialUserOp.PaymasterAndData = await GetPaymasterAndData(requestMessage.Id, partialUserOpHexified);
 
-            partialUserOp.Signature = await partialUserOp.HashAndSignUserOp(Config.entryPointAddress);
-            partialUserOpHexified = partialUserOp.EncodeUserOperation();
-
-            // Estimate gas with updated paymaster data
-            Debug.Log("Estimate gas with updated paymaster data...");
+            // Hash, sign and encode the user operation
 
-            var gasEstimates = await BundlerClient.EthEstimateUserOperationGas(Config.bundlerUrl, Config.thirdwebApiKey, requestMessage.Id, partialUserOpHexified, Config.entryPointAddress);
-            partialUserOp.CallGasLimit = new HexBigInteger(gasEstimates.CallGasLimit).Value;
-            partialUserOp.VerificationGasLimit = new HexBigInteger(gasEstimates.VerificationGas).Value;
-            partialUserOp.PreVerificationGas = new HexBigInteger(gasEstimates.PreVerificationGas).Value;
-
-            partialUserOp.Signature = await partialUserOp.HashAndSignUserOp(Config.entryPointAddress);
-            partialUserOpHexified = partialUserOp.EncodeUserOperation();
-
-            // Update paymaster data post estimates again
-            Debug.Log("Update paymaster data post estimates again...");
-
-            partialUserOp.PaymasterAndData = await GetPaymasterAndData(requestMessage.Id, partialUserOpHexified);
             partialUserOp.Signature = await partialUserOp.HashAndSignUserOp(Config.entryPointAddress);
             partialUserOpHexified = partialUserOp.EncodeUserOperation();
 
             // Send the user operation
-            Debug.Log("Send the user operation...");
 
             Debug.Log("Valid UserOp: " + JsonConvert.SerializeObject(partialUserOp));
             Debug.Log("Valid Encoded UserOp: " + JsonConvert.SerializeObject(partialUserOpHexified));
@@ -199,7 +180,6 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
             Debug.Log("UserOp Hash: " + userOpHash);
 
             // Wait for the transaction to be mined
-            Debug.Log("Wait for the transaction to be mined...");
 
             string txHash = null;
             while (txHash == null && Application.isPlaying)
@@ -211,7 +191,6 @@ private async Task<RpcResponseMessage> CreateUserOpAndSend(RpcRequestMessage req
             Debug.Log("Tx Hash: " + txHash);
 
             // Check if successful
-            Debug.Log("Check if successful...");
 
             var receipt = await new Web3(ThirdwebManager.Instance.SDK.session.RPC).Eth.Transactions.GetTransactionReceipt.SendRequestAsync(txHash);
             var decodedEvents = receipt.DecodeAllEvents<EntryPointContract.UserOperationEventEventDTO>();
diff --git a/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/UserOpUtils.cs b/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/UserOpUtils.cs
index 50a02751..231ef716 100644
--- a/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/UserOpUtils.cs
+++ b/Assets/Thirdweb/Core/Scripts/AccountAbstraction/Core/UserOpUtils.cs
@@ -44,5 +44,75 @@ public static UserOperationHexified EncodeUserOperation(this EntryPointContract.
                 signature = userOperation.Signature.ByteArrayToHexString()
             };
         }
+
+        public static int CalcPreVerificationGas(this EntryPointContract.UserOperation userOp, GasOverheads gasOverheads = null)
+        {
+            GasOverheads ov = gasOverheads ?? new GasOverheads();
+
+            userOp.Signature = new byte[ov.sigSize];
+            userOp.PreVerificationGas = 21000;
+
+            byte[] packed = userOp.PackUserOp(false);
+            int lengthInWord = (packed.Length + 31) / 32;
+
+            int callDataCost = 0;
+            foreach (byte b in packed)
+            {
+                callDataCost += (b == 0) ? ov.zeroByte : ov.nonZeroByte;
+            }
+
+            int totalGas = callDataCost + ov.fixedGas / ov.bundleSize + ov.perUserOp + ov.perUserOpWord * lengthInWord;
+
+            return totalGas;
+        }
+
+        public static byte[] PackUserOp(this EntryPointContract.UserOperation op, bool forSignature = true)
+        {
+            var abiEncode = new Nethereum.ABI.ABIEncode();
+            var sha3Keccak = new Nethereum.Util.Sha3Keccack();
+
+            if (forSignature)
+            {
+                return abiEncode.GetABIEncoded(
+                    op.Sender,
+                    op.Nonce,
+                    sha3Keccak.CalculateHash(op.InitCode),
+                    sha3Keccak.CalculateHash(op.CallData),
+                    op.CallGasLimit,
+                    op.VerificationGasLimit,
+                    op.PreVerificationGas,
+                    op.MaxFeePerGas,
+                    op.MaxPriorityFeePerGas,
+                    sha3Keccak.CalculateHash(op.PaymasterAndData)
+                );
+            }
+            else
+            {
+                return abiEncode.GetABIEncodedPacked(
+                    op.Sender,
+                    op.Nonce,
+                    op.InitCode,
+                    op.CallData,
+                    op.CallGasLimit,
+                    op.VerificationGasLimit,
+                    op.PreVerificationGas,
+                    op.MaxFeePerGas,
+                    op.MaxPriorityFeePerGas,
+                    op.PaymasterAndData,
+                    op.Signature
+                );
+            }
+        }
+    }
+
+    public class GasOverheads
+    {
+        public int fixedGas = 21000;
+        public int perUserOp = 18300;
+        public int perUserOpWord = 4;
+        public int zeroByte = 4;
+        public int nonZeroByte = 16;
+        public int bundleSize = 1;
+        public int sigSize = Constants.DUMMY_SIG_LENGTH;
     }
 }