diff --git a/js/models/PublicKeyRing.js b/js/models/PublicKeyRing.js
index 42e6fa626..dba051db9 100644
--- a/js/models/PublicKeyRing.js
+++ b/js/models/PublicKeyRing.js
@@ -14,17 +14,6 @@ var buffertools = bitcore.buffertools;
 var Storage     = imports.Storage || require('./Storage');
 var storage     = Storage.default();
 
-/*
- * This follow Electrum convetion, as described in
- * https://bitcointalk.org/index.php?topic=274182.0
- *
- * We should probably adopt the next standard once it's ready, as discussed in:
- * http://sourceforge.net/p/bitcoin/mailman/message/32148600/
- *
- */
-
-var PUBLIC_BRANCH = 'm/0/';
-var CHANGE_BRANCH = 'm/1/';
 
 function PublicKeyRing(opts) {
   opts = opts || {};
@@ -44,6 +33,22 @@ function PublicKeyRing(opts) {
   this.addressIndex=0;
 }
 
+/*
+ * This follow Electrum convetion, as described in
+ * https://bitcointalk.org/index.php?topic=274182.0
+ *
+ * We should probably adopt the next standard once it's ready, as discussed in:
+ * http://sourceforge.net/p/bitcoin/mailman/message/32148600/
+ *
+ */
+
+PublicKeyRing.PublicBranch = function (index) {
+  return 'm/0/'+index;
+};
+
+PublicKeyRing.ChangeBranch = function (index) {
+  return 'm/1/'+index;
+};
 
 PublicKeyRing.getRandomId = function () {
   return buffertools.toHex(coinUtil.generateNonce());
@@ -177,7 +182,7 @@ PublicKeyRing.prototype.getPubKeys = function (index, isChange) {
   var pubKeys = [];
   var l = this.copayersBIP32.length;
   for(var i=0; i<l; i++) {
-    var path = (isChange ? CHANGE_BRANCH : PUBLIC_BRANCH) + index;
+    var path = isChange ? PublicKeyRing.ChangeBranch(index) : PublicKeyRing.PublicBranch(index); 
     var bip32 = this.copayersBIP32[i].derive(path);
     pubKeys[i] = bip32.eckey.public;
   }
@@ -201,6 +206,7 @@ PublicKeyRing.prototype.getRedeemScript = function (index, isChange) {
   return script;
 };
 
+
 PublicKeyRing.prototype.getAddress = function (index, isChange) {
   this._checkIndexRange(index, isChange);
 
@@ -238,6 +244,21 @@ PublicKeyRing.prototype.getAddresses = function() {
   return ret;
 };
 
+PublicKeyRing.prototype.getRedeemScriptMap = function () {
+  var ret = {};
+
+  for (var i=0; i<this.changeAddressIndex; i++) {
+    ret[this.getAddress(i,true)] = this.getRedeemScript(i,true);
+  }
+
+  for (var i=0; i<this.addressIndex; i++) {
+    ret[this.getAddress(i)] = this.getRedeemScript(i);
+  }
+  return ret;
+};
+
+
+
 PublicKeyRing.prototype._checkInPRK = function(inPKR, ignoreId) {
 
 
diff --git a/js/models/TxProposals.js b/js/models/TxProposals.js
new file mode 100644
index 000000000..d823a4d5e
--- /dev/null
+++ b/js/models/TxProposals.js
@@ -0,0 +1,77 @@
+
+'use strict';
+
+
+var imports     = require('soop').imports();
+var bitcore     = require('bitcore');
+var coinUtil    = bitcore.util;
+var Transaction = bitcore.Transaction;
+var Builder = bitcore.TransactionBuilder;
+var buffertools = bitcore.buffertools;
+
+var Storage     = imports.Storage || require('./Storage');
+var storage     = Storage.default();
+
+/*
+ * This follow Electrum convetion, as described in
+ * https://bitcointalk.org/index.php?topic=274182.0
+ *
+ * We should probably adopt the next standard once it's ready, as discussed in:
+ * http://sourceforge.net/p/bitcoin/mailman/message/32148600/
+ *
+ */
+
+var PUBLIC_BRANCH = 'm/0/';
+var CHANGE_BRANCH = 'm/1/';
+
+function TxProposals(opts) {
+  opts = opts || {};
+
+  this.network = opts.networkName === 'livenet' ? 
+      bitcore.networks.livenet : bitcore.networks.testnet;
+
+  this.publicKeyRing = opts.publicKeyRing;
+  this.requiredCopayers = opts.requiredCopayers || 3;
+  this.txs = [];
+  this.dirty = 1;
+}
+
+
+TxProposals.prototype.list = function() {
+  var ret = [];
+
+  this.txs.forEach(function(tx) {
+  });
+};
+
+TxProposals.prototype.create = function(toAddress, amountSat, utxos, onePrivKey) {
+  var pkr = this.publicKeyRing; 
+
+  if (! pkr.isComplete() ) {
+    throw new Error('publicKeyRing is not complete');
+  }
+
+  var opts = {
+    remainderOut: { address: pkr.generateAddress(true) }
+  };
+
+  var b = new Builder(opts)
+    .setUnspent(utxos)
+    .setHashToScriptMap(pkr.getRedeemScriptMap())
+    .setOutputs([{address: toAddress, amountSat: amountSat}])
+    ;
+
+  if (onePrivKey) {
+    b.sign([onePrivKey]);
+  }
+
+  var tx = b.build();
+  var txHex = tx.serialize();
+  this.txs.push(txHex);    
+  return txHex;
+};
+
+TxProposals.prototype.sign = function(index) {
+};
+
+module.exports = require('soop')(TxProposals);
diff --git a/test/test.publickeyring.js b/test/test.publickeyring.js
index 9c4bb2cac..9fd1d48a5 100644
--- a/test/test.publickeyring.js
+++ b/test/test.publickeyring.js
@@ -268,6 +268,24 @@ describe('PublicKeyRing model', function() {
     }
     w.isComplete().should.equal(true);
   });
+
+
+  it('#getRedeemScriptMap check tests', function () {
+    var k = createW();
+    var w = k.w;
+
+    for(var i=0; i<2; i++)
+      w.generateAddress(true);
+    for(var i=0; i<3; i++)
+      w.generateAddress(false);
+
+    var m = w.getRedeemScriptMap();
+    Object.keys(m).length.should.equal(5);
+    Object.keys(m).forEach(function (k) {
+      should.exist(m[k]);
+    });
+  });
+
 });
 
 
diff --git a/test/test.txproposal.js b/test/test.txproposal.js
new file mode 100644
index 000000000..adcafbc0a
--- /dev/null
+++ b/test/test.txproposal.js
@@ -0,0 +1,127 @@
+'use strict';
+
+var chai           = chai || require('chai');
+var should         = chai.should();
+var bitcore        = bitcore || require('bitcore');
+var Transaction        = bitcore.Transaction;
+var buffertools    = bitcore.buffertools;
+var WalletKey    = bitcore.WalletKey;
+var Key    = bitcore.Key;
+var BIP32    = bitcore.BIP32;
+var bignum         = bitcore.bignum;
+var networks         = bitcore.networks;
+var copay          = copay || require('../copay');
+var fakeStorage    = copay.FakeStorage;
+var TxProposals    = copay.TxProposals || require('../js/models/TxProposal');
+var PublicKeyRing  = (typeof process.versions === 'undefined') ? copay.PublicKeyRing :
+  require('soop').load('../js/models/PublicKeyRing', {Storage: fakeStorage});
+
+var config = {
+  networkName:'livenet',
+};
+
+var unspentTest = [
+    {
+      "address": "dummy",
+      "scriptPubKey": "dummy",
+      "txid": "2ac165fa7a3a2b535d106a0041c7568d03b531e58aeccdd3199d7289ab12cfc1",
+      "vout": 1,
+      "amount": 10,
+      "confirmations":7
+    }
+];
+
+var createW = function (bip32s) {
+  var w = new PublicKeyRing(config);
+  should.exist(w);
+
+  for(var i=0; i<5; i++) {
+    if (bip32s) {
+      var b=bip32s[i];
+      w.addCopayer(b?b.extendedPrivateKeyString():null);
+    }
+    else 
+      w.addCopayer();
+  }
+  w.generateAddress(true);
+  w.generateAddress(true);
+  w.generateAddress(true);
+  w.generateAddress(false);
+  w.generateAddress(false);
+  
+  return w;
+};
+
+
+describe('TxProposals model', function() {
+
+  it('should create an instance', function () {
+    var w = new TxProposals({
+      networkName: config.networkName
+    });
+    should.exist(w);
+    w.network.name.should.equal('livenet');
+  });
+
+  it('#create', function () {
+    var w = new TxProposals({
+      networkName: config.networkName,
+      publicKeyRing: createW(),
+    });
+    should.exist(w);
+    w.network.name.should.equal('livenet');
+
+    unspentTest[0].address        = w.publicKeyRing.getAddress(1, true);
+    unspentTest[0].scriptPubKey   = w.publicKeyRing.getRedeemScript(1, true).getBuffer();
+
+    var txHex = w.create(
+      '15q6HKjWHAksHcH91JW23BJEuzZgFwydBt', 
+      bignum('123456789'), 
+      unspentTest
+    );
+    should.exist(txHex);
+
+    var t2=new Transaction();
+    t2.parse(txHex);
+    t2.isComplete().should.equal(false);
+  });
+
+  it('#create. Singing with derivate keys', function () {
+
+    var oneBIP32 = new BIP32(config.networkName);
+
+    var w = new TxProposals({
+      networkName: config.networkName,
+      publicKeyRing: createW([oneBIP32]),
+    });
+    should.exist(w);
+    w.network.name.should.equal('livenet');
+
+
+    for (var isChange=0; isChange<2; isChange++) {
+      for (var index=0; index<3; index++) {
+        unspentTest[0].address        = w.publicKeyRing.getAddress(index, isChange);
+        unspentTest[0].scriptPubKey   = w.publicKeyRing.getRedeemScript(index, isChange).getBuffer();
+
+        var derivedBip32 = oneBIP32.derive( isChange ? PublicKeyRing.ChangeBranch(index):PublicKeyRing.PublicBranch(index) );
+        var wk = new WalletKey({network: networks.livenet});
+        var p = derivedBip32.eckey.private.toString('hex');
+        wk.fromObj({priv: p});
+
+        var txHex = w.create(
+          '15q6HKjWHAksHcH91JW23BJEuzZgFwydBt', 
+          bignum('123456789'), 
+          unspentTest,
+          wk
+        );
+        should.exist(txHex);
+        var t2=new Transaction();
+        t2.parse(txHex);
+        t2.isComplete().should.equal(false);
+        t2.countInputMissingSignatures(0).should.equal(2);
+      }
+    }
+
+  });
+});
+