diff --git a/src/transaction.js b/src/transaction.js
index b7c6f7f..fa1b18a 100644
--- a/src/transaction.js
+++ b/src/transaction.js
@@ -4,7 +4,6 @@ var crypto = require('./crypto')
 var typeForce = require('typeforce')
 var opcodes = require('./opcodes')
 
-var Address = require('./address')
 var Script = require('./script')
 
 function Transaction () {
@@ -104,16 +103,6 @@ Transaction.isCoinbaseHash = function (buffer) {
   })
 }
 
-/**
- * Create a new txIn.
- *
- * Can be called with any of:
- *
- * - A transaction and an index
- * - A transaction hash and an index
- *
- * Note that this method does not sign the created input.
- */
 Transaction.prototype.addInput = function (hash, index, sequence, script) {
   if (sequence === undefined || sequence === null) {
     sequence = Transaction.DEFAULT_SEQUENCE
@@ -121,13 +110,6 @@ Transaction.prototype.addInput = function (hash, index, sequence, script) {
 
   script = script || Script.EMPTY
 
-  if (typeof hash === 'string') {
-    // TxId hex is big-endian, we need little-endian
-    hash = bufferutils.reverse(new Buffer(hash, 'hex'))
-  } else if (hash instanceof Transaction) {
-    hash = hash.getHash()
-  }
-
   typeForce('Buffer', hash)
   typeForce('Number', index)
   typeForce('Number', sequence)
@@ -144,26 +126,7 @@ Transaction.prototype.addInput = function (hash, index, sequence, script) {
   }) - 1)
 }
 
-/**
- * Create a new txOut.
- *
- * Can be called with:
- *
- * - A base58 address string and a value
- * - An Address object and a value
- * - A scriptPubKey Script and a value
- */
 Transaction.prototype.addOutput = function (scriptPubKey, value) {
-  // Attempt to get a valid address if it's a base58 address string
-  if (typeof scriptPubKey === 'string') {
-    scriptPubKey = Address.fromBase58Check(scriptPubKey)
-  }
-
-  // Attempt to get a valid script if it's an Address object
-  if (scriptPubKey instanceof Address) {
-    scriptPubKey = scriptPubKey.toOutputScript()
-  }
-
   typeForce('Script', scriptPubKey)
   typeForce('Number', value)
 
@@ -201,10 +164,10 @@ Transaction.prototype.clone = function () {
 /**
  * Hash transaction for signing a specific input.
  *
- * Bitcoin uses a different hash for each signed transaction input. This
- * method copies the transaction, makes the necessary changes based on the
- * hashType, serializes and finally hashes the result. This hash can then be
- * used to sign the transaction input in question.
+ * Bitcoin uses a different hash for each signed transaction input.
+ * This method copies the transaction, makes the necessary changes based on the
+ * hashType, and then hashes the result.
+ * This hash can then be used to sign the provided transaction input.
  */
 Transaction.prototype.hashForSignature = function (inIndex, prevOutScript, hashType) {
   typeForce('Number', inIndex)
diff --git a/src/transaction_builder.js b/src/transaction_builder.js
index 8a58e9a..fb8b852 100644
--- a/src/transaction_builder.js
+++ b/src/transaction_builder.js
@@ -2,6 +2,7 @@ var assert = require('assert')
 var ops = require('./opcodes')
 var scripts = require('./scripts')
 
+var Address = require('./address')
 var ECPubKey = require('./ecpubkey')
 var ECSignature = require('./ecsignature')
 var Script = require('./script')
@@ -188,6 +189,16 @@ TransactionBuilder.prototype.addOutput = function (scriptPubKey, value) {
     return (input.hashType & 0x1f) === Transaction.SIGHASH_SINGLE
   }), 'No, this would invalidate signatures')
 
+  // Attempt to get a valid address if it's a base58 address string
+  if (typeof scriptPubKey === 'string') {
+    scriptPubKey = Address.fromBase58Check(scriptPubKey)
+  }
+
+  // Attempt to get a valid script if it's an Address object
+  if (scriptPubKey instanceof Address) {
+    scriptPubKey = scriptPubKey.toOutputScript()
+  }
+
   return this.tx.addOutput(scriptPubKey, value)
 }
 
diff --git a/test/transaction.js b/test/transaction.js
index c9a6aa4..4a64493 100644
--- a/test/transaction.js
+++ b/test/transaction.js
@@ -2,7 +2,6 @@
 
 var assert = require('assert')
 
-var Address = require('../src/address')
 var Transaction = require('../src/transaction')
 var Script = require('../src/script')
 
@@ -63,21 +62,10 @@ describe('Transaction', function () {
   })
 
   describe('addInput', function () {
-    // FIXME: not as pretty as could be
-    // Probably a bit representative of the API
-    var prevTxHash, prevTxId, prevTx
+    var prevTxHash
     beforeEach(function () {
       var f = fixtures.valid[0]
-      prevTx = Transaction.fromHex(f.hex)
-      prevTxHash = prevTx.getHash()
-      prevTxId = prevTx.getId()
-    })
-
-    it('accepts a transaction id', function () {
-      var tx = new Transaction()
-      tx.addInput(prevTxId, 0)
-
-      assert.deepEqual(tx.ins[0].hash, prevTxHash)
+      prevTxHash = new Buffer(f.hash, 'hex')
     })
 
     it('accepts a transaction hash', function () {
@@ -87,13 +75,6 @@ describe('Transaction', function () {
       assert.deepEqual(tx.ins[0].hash, prevTxHash)
     })
 
-    it('accepts a Transaction object', function () {
-      var tx = new Transaction()
-      tx.addInput(prevTx, 0)
-
-      assert.deepEqual(tx.ins[0].hash, prevTxHash)
-    })
-
     it('returns an index', function () {
       var tx = new Transaction()
       assert.equal(tx.addInput(prevTxHash, 0), 0)
@@ -127,43 +108,19 @@ describe('Transaction', function () {
   })
 
   describe('addOutput', function () {
-    // FIXME: not as pretty as could be
-    // Probably a bit representative of the API
-    var destAddressB58, destAddress, destScript
-    beforeEach(function () {
-      destAddressB58 = '15mMHKL96tWAUtqF3tbVf99Z8arcmnJrr3'
-      destAddress = Address.fromBase58Check(destAddressB58)
-      destScript = destAddress.toOutputScript()
-    })
-
-    it('accepts an address string', function () {
-      var tx = new Transaction()
-      tx.addOutput(destAddressB58, 40000)
-
-      assert.deepEqual(tx.outs[0].script, destScript)
-      assert.equal(tx.outs[0].value, 40000)
-    })
-
-    it('accepts an Address', function () {
-      var tx = new Transaction()
-      tx.addOutput(destAddress, 40000)
-
-      assert.deepEqual(tx.outs[0].script, destScript)
-      assert.equal(tx.outs[0].value, 40000)
-    })
-
-    it('accepts a scriptPubKey', function () {
-      var tx = new Transaction()
-      tx.addOutput(destScript, 40000)
+    fixtures.valid.forEach(function (f) {
+      it('should add the outputs for ' + f.id + ' correctly', function () {
+        var tx = new Transaction()
 
-      assert.deepEqual(tx.outs[0].script, destScript)
-      assert.equal(tx.outs[0].value, 40000)
-    })
+        f.raw.outs.forEach(function (txOut, i) {
+          var scriptPubKey = Script.fromASM(txOut.script)
+          var j = tx.addOutput(scriptPubKey, txOut.value)
 
-    it('returns an index', function () {
-      var tx = new Transaction()
-      assert.equal(tx.addOutput(destScript, 40000), 0)
-      assert.equal(tx.addOutput(destScript, 40000), 1)
+          assert.equal(i, j)
+          assert.equal(tx.outs[i].script, scriptPubKey)
+          assert.equal(tx.outs[i].value, txOut.value)
+        })
+      })
     })
   })
 
@@ -190,9 +147,8 @@ describe('Transaction', function () {
     fixtures.valid.forEach(function (f) {
       it('should return the id for ' + f.id, function () {
         var tx = Transaction.fromHex(f.hex)
-        var actual = tx.getId()
 
-        assert.equal(actual, f.id)
+        assert.equal(tx.getId(), f.id)
       })
     })
   })
@@ -201,9 +157,8 @@ describe('Transaction', function () {
     fixtures.valid.forEach(function (f) {
       it('should return the hash for ' + f.id, function () {
         var tx = Transaction.fromHex(f.hex)
-        var actual = tx.getHash().toString('hex')
 
-        assert.equal(actual, f.hash)
+        assert.deepEqual(tx.getHash().toString('hex'), f.hash)
       })
     })
   })
diff --git a/test/transaction_builder.js b/test/transaction_builder.js
index 11172e5..350011b 100644
--- a/test/transaction_builder.js
+++ b/test/transaction_builder.js
@@ -2,6 +2,7 @@
 
 var assert = require('assert')
 
+var Address = require('../src/address')
 var BigInteger = require('bigi')
 var ECKey = require('../src/eckey')
 var Script = require('../src/script')
@@ -62,8 +63,8 @@ describe('TransactionBuilder', function () {
     txb = new TransactionBuilder()
 
     prevTx = new Transaction()
-    prevTx.addOutput('1BgGZ9tcN4rm9KBzDn7KprQz87SZ26SAMH', 0)
-    prevTx.addOutput('1cMh228HTCiwS8ZsaakH8A8wze1JR5ZsP', 1)
+    prevTx.addOutput(Address.fromBase58Check('1BgGZ9tcN4rm9KBzDn7KprQz87SZ26SAMH').toOutputScript(), 0)
+    prevTx.addOutput(Address.fromBase58Check('1cMh228HTCiwS8ZsaakH8A8wze1JR5ZsP').toOutputScript(), 1)
     prevTxHash = prevTx.getHash()
 
     privKey = new ECKey(BigInteger.ONE, false)
@@ -121,6 +122,33 @@ describe('TransactionBuilder', function () {
   })
 
   describe('addOutput', function () {
+    it('accepts an address string and value', function () {
+      var vout = txb.addOutput(privAddress.toBase58Check(), 1000)
+      assert.equal(vout, 0)
+
+      var txout = txb.tx.outs[0]
+      assert.deepEqual(txout.script, privScript)
+      assert.equal(txout.value, 1000)
+    })
+
+    it('accepts an Address object and value', function () {
+      var vout = txb.addOutput(privAddress, 1000)
+      assert.equal(vout, 0)
+
+      var txout = txb.tx.outs[0]
+      assert.deepEqual(txout.script, privScript)
+      assert.equal(txout.value, 1000)
+    })
+
+    it('accepts a ScriptPubKey and value', function () {
+      var vout = txb.addOutput(privScript, 1000)
+      assert.equal(vout, 0)
+
+      var txout = txb.tx.outs[0]
+      assert.deepEqual(txout.script, privScript)
+      assert.equal(txout.value, 1000)
+    })
+
     it('throws if SIGHASH_ALL has been used to sign any existing scriptSigs', function () {
       txb.addInput(prevTxHash, 0)
       txb.addOutput(privScript, 2000)