I would like a form that would supply clients with an estimated cost based on the price x quantity of product.

Yes it is possible to achieve your requirement by adding payment tool in form to list your products. I would suggest you to please take a look at our "TEMPLATES" section where we have hundreds of pre-built order form and see if any of them fits into your requirement. 

You can use any of the form templates and customize it to list your own products. The following guide should help you how to use form templates:   https://www.jotform.com/help/106-How-to-Use-Form-Templates

Hope this helps.

Do get back to us if you have any questions.