Paypal Standard: How to allow users to deposit certain amount?

Hello, thx in advance to anyone who attempts this little problem.

I'm creating a form for a seafood restaurant. They want to sell platters on their site and I have for the most part completed it.

When a customer buys a platter to take home they need to pay a deposit on the platter itself (the ceramic plate)

All the products include tax and that is represented on the total pricing but I don't want the deposit to include tax.

It needs to be done in a way so that for every platter purchased their is a $50 deposit included(without tax)

also, the client wants the deposit price separated from the totals in the total amount section.

example:

Subtotal:  $90.00 CADTax:  $11.70 CAD

Deposit                                    $50.00 CAD           (again, this needs to be tax free, on its own line like in this example)

Total:  $151.70 CAD

Unfortunately, there does not seem to be a way to allow users do deposit certain amount with the payment integrations, at least while selling products. 

I think you will need to set up your products in a different way and manually calculate the total amount by using the Form Calculation widget. 

Check the guides below for reference. 

How-to-Perform-Calculation-in-the-Form

How-to-Pass-a-Calculation-to-a-Payment-Field

This guide will also help you: How-to-Assign-Calculation-Value

This way you can send the custom amount ($50) to the payment field and your users will be charged for that amount, once this deposit has been charged then you may send another link to your users to complete the payment with other amount. 

You will need to create a second form or you may even use the same if you want, but you will need to pre-populate the form with the previously submitted data, here is a guide that will help you with that: Prepopulating-Fields-to-Your-JotForm-via-URL-Parameters

This way you will have the next workflow: 

1. Your users will fill out the first form and they will see the deposit amount and the difference. 

2. You will take the needed data including the pending amount and will generate the link and include it in an Email Auto-Responder that will be sent to your submitter.

3. Your submitter will receive an email with the submitted data, here will be included the link to the second form where they will complete the payment, once they open the link all the info will be pre-populated and they only need to submit the form and pay. 

This way you will allow them to pay you a deposit and complete the payment with the pending amount on a later date or when they receive the product. 

Please give it a try and let us know if you have any question, we will be glad to help you.