Thank you for getting back and providing us with more details about your concern, @arretx.

You can record it in QuickBooks Desktop as upfront deposits or retainers. Then, you can apply this deposit to your invoices. 

To create a liability account:

1. Go to the Lists menu and click on Chart of Accounts.
2. Click on New from the pop-up menu.
3. Select Other Current Liability as the Account Type.
4. Set an account name.
5. Click on Ok.

To create an upfront deposit item:

1. Go to the Lists menu and click on Item List.
2. In the Item List window, right-click and select New from the pop-up menu.
3. From the Type dropdown menu, select the purpose of the deposits you collect.
4. You can select Service if you collect upfront deposits for services, or Other Charge if you collect upfront deposits for products.
5. Set a name. 
6. Select the Upfront Deposit liability account you created from the Account drop-down list.
7. Click on Ok.

Here's how to record upfront deposits or retainers you receive: 

1. From the Customers menu, select Enter Sales Receipts.
2. From the Customer:Job drop-down list, select the customer or job.
3. If the Deposit To field appears, select the account into which to deposit the funds.
4. Enter all the information needed.
5. Click on Save and close.

For detailed guidance with setting up, recording, and managing upfront deposits, check out this article: Manage upfront deposits or retainers. 

See this article on how to receive payments you receive from your customers in QuickBooks Desktop: Record an invoice payment. 

Let me know if you have further questions about recording your transactions. I'm always here to help. Have a great rest of the day!