# Amount

Source: https://developer.avalara.com/vat-ecom/transactions/certification-requirements/amount/

**Element type:** Required

**Endpoints/models used:** [LineItemModel](https://developer.avalara.com/api-reference/avatax/rest/v2/models/LineItemModel/)

Your UI must include a method for allowing users to specify a total amount for the line item in a transaction. The amount represents the total amount of money that changed hands from the customer (represented by the `customerCode` field) to the company (represented by the `companyCode`) field. In addition, this amount must be in the currency specified by the document's `currencyCode`. When determining the amount to enter for this value, keep in mind the value of the `isTaxIncluded` flag.

For sale transactions, this value must be positive. It indicates the amount of money paid by the customer to the company. For credit memos or refund transactions, this value must be negative.

Specify item amounts using the `amount` field on the [LineItemModel](https://developer.avalara.com/api-reference/avatax/rest/v2/models/LineItemModel/). This field is required for users.

[![Closed](https://avalara-devdocs-prod.mcoutput.com/vat-ecom/Skins/Default/Stylesheets/Images/transparent.gif)View example](javascript:void\(0\);)

```
{    ...,  "lines": [    {      "number": "1",      "quantity": 1,      "amount": 100,      "taxCode": "PS081282",      "itemCode": "Y0001",      "description": "Yarn"    }  ],  ...} 
```