What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
Unfortunately, it's not possible to automatically removed sold items in the Paypal integration. You have to manually do it in the configuration.
If you want to control the inventory and disable the item once all available items are solved, you can use our inventory widget:
You will have to calculate the items by its price, here's how: https://www.jotform.com/help/259-How-to-perform-calculation-in-the-form.
After that, you can pass the total calculation to the Paypal field. Here's how: http://www.jotform.com/help/275-How-to-pass-a-calculation-to-a-payment-field.
Let us know if you need help with this.