diff --git a/api/types.go b/api/types.go
index 8bf1cd4b..4047c3b1 100644
--- a/api/types.go
+++ b/api/types.go
@@ -265,6 +265,7 @@ type Utxo struct {
 	Confirmations int     `json:"confirmations"`
 	Address       string  `json:"address,omitempty"`
 	Path          string  `json:"path,omitempty"`
+	Locktime      uint32  `json:"lockTime,omitempty"`
 }
 
 // Utxos is array of Utxo
diff --git a/configs/coins/bitcoin_testnet.json b/configs/coins/bitcoin_testnet.json
index 5e72c74d..f892a6a1 100644
--- a/configs/coins/bitcoin_testnet.json
+++ b/configs/coins/bitcoin_testnet.json
@@ -59,10 +59,7 @@
       "xpub_magic_segwit_p2sh": 71979618,
       "xpub_magic_segwit_native": 73342198,
       "slip44": 1,
-      "additional_params": {
-        "alternativeEstimateFee": "whatthefee",
-        "alternativeEstimateFeeParams": "{\"url\": \"https://whatthefee.io/data.json\", \"periodSeconds\": 60}"
-      }
+      "additional_params": {}
     }
   },
   "meta": {
diff --git a/db/rocksdb.go b/db/rocksdb.go
index 735402e3..3c1e65f4 100644
--- a/db/rocksdb.go
+++ b/db/rocksdb.go
@@ -19,7 +19,7 @@ import (
 	"github.com/tecbot/gorocksdb"
 )
 
-const dbVersion = 4
+const dbVersion = 5
 
 const packedHeightBytes = 4
 const maxAddrDescLen = 1024
@@ -383,11 +383,20 @@ type TxAddresses struct {
 	Outputs []TxOutput
 }
 
+// Utxo holds information about unspent transaction output
+type Utxo struct {
+	BtxID    []byte
+	Vout     int32
+	Height   uint32
+	ValueSat big.Int
+}
+
 // AddrBalance stores number of transactions and balances of an address
 type AddrBalance struct {
 	Txs        uint32
 	SentSat    big.Int
 	BalanceSat big.Int
+	Utxos      []Utxo
 }
 
 // ReceivedSat computes received amount from total balance and sent amount
@@ -422,7 +431,7 @@ func (d *RocksDB) GetAndResetConnectBlockStats() string {
 func (d *RocksDB) processAddressesBitcoinType(block *bchain.Block, addresses addressesMap, txAddressesMap map[string]*TxAddresses, balances map[string]*AddrBalance) error {
 	blockTxIDs := make([][]byte, len(block.Txs))
 	blockTxAddresses := make([]*TxAddresses, len(block.Txs))
-	// first process all outputs so that inputs can point to txs in this block
+	// first process all outputs so that inputs can refer to txs in this block
 	for txi := range block.Txs {
 		tx := &block.Txs[txi]
 		btxID, err := d.chainParser.PackTxid(tx.Txid)