Go the Dashboard > Contacts > Select contact for advance payment > Click on Payment icon > Enter the amount and select the Payment type and save.

you can also add additional information in "Notes"

You can verify the same from the outstanding amount.

Below are the steps to add Advance Payment For Customers in Moon Invoice with attachments :-

1. Open Moon Invoice application on your device or in the browser from this link

2. Navigate Contact section.

3. Select contact for advance payment.

4. Check the outstanding amount and Click on Payment icon. 

5. Select the Payment type, Enter the amount and click on save.

6. We can also add additional information in "Notes" (Optional)

7. We can verify the advance payment from the outstanding amount.

8. Create a invoice and check the outstanding amount in invoice.

Note - Amount will automatically get deducted when you create invoice for the Contact and it will be reduce the outstanding amount too.