diff --git a/utilities/wallet-tester/src/common/components/TxBuilder.tsx b/utilities/wallet-tester/src/common/components/TxBuilder.tsx
index 3f06a0d9f7..fe29b8f31b 100644
--- a/utilities/wallet-tester/src/common/components/TxBuilder.tsx
+++ b/utilities/wallet-tester/src/common/components/TxBuilder.tsx
@@ -354,9 +354,10 @@ function TxBuilder({ utxos, addresses, onSubmit: onPropSubmit = noop }: Props) {
         onRemoveClick={() => resetField("networkId")}
         render={() => (
           <Input
-            type="text"
-            disabled={true}
-            placeholder="Auto generated"
+            type="number"
+            min={0}
+            max={1}
+            placeholder="0: testnet, 1: mainnet"
             label="Network ID"
             formRegister={register("networkId")}
           />
diff --git a/utilities/wallet-tester/src/common/helpers/buildUnsignedTx.ts b/utilities/wallet-tester/src/common/helpers/buildUnsignedTx.ts
index 4c12ef8e3d..59f981467b 100644
--- a/utilities/wallet-tester/src/common/helpers/buildUnsignedTx.ts
+++ b/utilities/wallet-tester/src/common/helpers/buildUnsignedTx.ts
@@ -11,6 +11,7 @@ import {
   GeneralTransactionMetadata,
   Int,
   LinearFee,
+  NetworkId,
   RewardAddress,
   StakeCredential,
   StakeDelegation,
@@ -148,7 +149,7 @@ export default async function buildUnsignedTx(
 
   // #7 add auxiliary data hash
   if (builder.auxiliaryDataHash) {
-    // auto generated
+    // note: the hash will be set after building auxillary data
   }
 
   // #8 add validity interval start
@@ -171,11 +172,6 @@ export default async function buildUnsignedTx(
     txBuilder.add_required_signer(Ed25519KeyHash.from_hex(stakeCred));
   }
 
-  // #15 add network id
-  if (builder.networkId) {
-    // auto generated
-  }
-
   // aux data
   const auxMetadata = AuxiliaryData.new();
   const txMetadata = GeneralTransactionMetadata.new();
@@ -212,6 +208,7 @@ export default async function buildUnsignedTx(
 
   if (txMetadata.len()) {
     auxMetadata.set_metadata(txMetadata);
+    txBuilder.set_auxiliary_data(auxMetadata);
   }
 
   // generate fee incase too much ADA provided for fee
@@ -221,7 +218,15 @@ export default async function buildUnsignedTx(
   }
 
   // build a full transaction, passing in empty witness set
-  const unsignedTx = Transaction.new(txBuilder.build(), TransactionWitnessSet.new(), auxMetadata);
+  const txBody = txBuilder.build();
+  
+  // #15 add network id
+  if (builder.networkId && [0, 1].includes(Number(builder.networkId))) {
+    const networkId = Number(builder.networkId) === 0 ? NetworkId.testnet() : NetworkId.mainnet()
+    txBody.set_network_id(networkId);
+  }
+
+  const unsignedTx = Transaction.new(txBody, TransactionWitnessSet.new(), auxMetadata);
 
   return unsignedTx;
 }
diff --git a/utilities/wallet-tester/src/common/helpers/getCardano.ts b/utilities/wallet-tester/src/common/helpers/getCardano.ts
index 68f491b6b4..b6e326b551 100644
--- a/utilities/wallet-tester/src/common/helpers/getCardano.ts
+++ b/utilities/wallet-tester/src/common/helpers/getCardano.ts
@@ -1,9 +1,14 @@
+import { pickBy } from "lodash-es";
 import type { WalletCollections } from "types/cardano";
 
 export default function getCardano<T extends string | undefined>(
   walletName?: T
 ): T extends string ? WalletCollections[string] : WalletCollections {
-  return (walletName ? globalThis.cardano[walletName] : globalThis.cardano) as T extends string
+  return (walletName ? globalThis.cardano[walletName] : filterPolluteObjects(globalThis.cardano)) as T extends string
     ? WalletCollections[string]
     : WalletCollections;
 }
+
+function filterPolluteObjects(cardano: any): WalletCollections {
+  return pickBy(cardano, (v) => typeof v === "object" && "enable" in v)
+}