Modify fee calculations for tx building

Sources/Stratis.Bitcoin.Features.Wallet/DeStreamWalletManager.cs

@@ -110,5 +110,14 @@ namespace Stratis.Bitcoin.Features.Wallet
 
             return newAddress;
         }
+
+        public IEnumerable<string> GetOwnAddresses(WalletAccountReference accountReference)
+        {
+            return GetAccounts(accountReference.WalletName)
+                .Single(q => q.Name == accountReference.AccountName).ExternalAddresses
+                .Select(q => q.Address).Concat(GetAccounts(accountReference.WalletName)
+                    .Single(q => q.Name == accountReference.AccountName).InternalAddresses
+                    .Select(q => q.Address));
+        }
     }
 }
\ No newline at end of file

Sources/Stratis.Bitcoin.Features.Wallet/DeStreamWalletTransactionHandler.cs

-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Security;
@@ -33,7 +33,10 @@ namespace Stratis.Bitcoin.Features.Wallet
         /// <inheritdoc />
         protected override void AddFee(TransactionBuildContext context)
         {
-            long fee = Convert.ToInt64(context.Recipients.Sum(p => p.Amount) * this.DeStreamNetwork.FeeRate);
+            var fundTransfers = context.Recipients.Where(p => !(this.walletManager as IDeStreamWalletManager).GetOwnAddresses(context.AccountReference)
+                .Contains(p.ScriptPubKey.GetDestinationAddress(this.network).ToString()));
+
+            long fee = Convert.ToInt64(fundTransfers.Sum(p => p.Amount) * this.DeStreamNetwork.FeeRate);
             context.TransactionFee = fee;
             context.TransactionBuilder.SendFees(fee);
         }

Sources/Stratis.Bitcoin.Features.Wallet/Interfaces/IDeStreamWalletManager.cs

-namespace Stratis.Bitcoin.Features.Wallet.Interfaces
+using System.Collections.Generic;
+
+namespace Stratis.Bitcoin.Features.Wallet.Interfaces
 {
     public interface IDeStreamWalletManager : IWalletManager
     {
@@ -8,5 +10,7 @@
         void ProcessGenesisBlock();
 
         HdAddress CreateAddress(WalletAccountReference accountReference);
+
+        IEnumerable<string> GetOwnAddresses(WalletAccountReference accountReference);
     }
 }
\ No newline at end of file