# Get Signed Transaction

## **Option 1: Write your function:** Get Signed Transaction

After [Step 1](https://docs.tronsave.io/developer/rest-api-v0/buy-on-rest-api/use-signed-transaction/estimate-trx), you will get the cost of the buy order. Then you will sing `transactionBuilder` to create a transfer transaction with an amount transfer equal `estimate_trx` from the buyer's address to the fund of the Tronsave market:  

```tsx
const dataSendTrx = await tronWeb.transactionBuilder.sendTrx('TRONSAVE_FUND_ADDRESS', estimate_trx, 'BUYER_ADDRESS')
const signed_tx = await tronWeb.trx.sign(dataSendTrx, 'PRIVATE_KEY');
```

{% hint style="info" %}

* change <mark style="color:blue;">`BUYER_ADDRESS`</mark> Is the buyer's public address&#x20;
* change <mark style="color:blue;">`PRIVATE_KEY`</mark>  Is the buyer's private key
* change <mark style="color:blue;">`TRONSAVE_FUND_ADDRESS`</mark> Is our Tronsave fund address on the mainnet
  {% endhint %}

Our Tronsave fund address is

{% tabs %}
{% tab title="Mainnet" %}

```
TWZEhq5JuUVvGtutNgnRBATbF8BnHGyn4S
```

{% endtab %}
{% endtabs %}

## **Option 2:** Use Tronsave Get Signed Transaction API

#### <mark style="color:orange;">`POST`</mark>  `https://api.tronsave.io/v0/signed-tx` <a href="#api-method" id="api-method"></a>

Rate limi&#x74;***: 15** requests per **1** second*

#### Request params <a href="#request-params" id="request-params"></a>

<table><thead><tr><th width="166.33333333333331">Field</th><th width="112">Position</th><th width="110">Type</th><th width="101">Required</th><th>Description</th></tr></thead><tbody><tr><td>address</td><td>body</td><td>string</td><td>true</td><td>The buyer's public address </td></tr><tr><td>private_key</td><td>body</td><td>string</td><td>true</td><td>The buyer's private key</td></tr><tr><td>estimate_trx</td><td>body</td><td>number</td><td>true</td><td>The amount of TRX to be paid is calculated in SUN.(estimate_trx <em>in</em> <a href="estimate-trx"><em><strong>Step 1</strong></em></a>)</td></tr></tbody></table>

#### Request params example <a href="#request-params-example" id="request-params-example"></a>

```javascript
{
    "address": "TM6ZeEgpefyGWeMLuzSbfqTGkPv8Z65432",
    "private_key": "{{yourprivateKey}}",
    "estimate_trx": 13500000 //from Step1
 }
```

#### Responses <a href="#responses" id="responses"></a>

```javascript
{
      "visible": false,
      "txID": "446eed36e31249b98b201db2e81a3825b185f1a3d8b2fea348b24fc021e58e0d",
      "raw_data": {
        "contract": [
          {
            "parameter": {
              "value": {
                "amount": 13500000,
                "owner_address": "417a0d868d1418c9038584af1252f85d486502eec0",
                "to_address": "41055756f33f419278d9ea059bd2b21120e6add748"
              },
              "type_url": "type.googleapis.com/protocol.TransferContract"
            },
            "type": "TransferContract"
          }
        ],
        "ref_block_bytes": "0713",
        "ref_block_hash": "6c5f7686f4176139",
        "expiration": 1691465106000,
        "timestamp": 1691465046758
      },
      "raw_data_hex": "0a02071322086c5f7686f417613940d084b5999d315a68080112640a2d747970652e676f6f676c65617069732e636f6d2f70726f746f636f6c2e5472616e73666572436f6e747261637412330a15417a0d868d1418c9038584af1252f85d486502eec0121541055756f33f419278d9ea059bd2b21120e6add74818e0fcb70670e6b5b1999d31",
      "signature": ["xxxxxxxxx"]
    }
```