Wondering if JotForm is right for my client

My client has forms he has created that can be customized for his customers. He is wanting to find a place that he can have his forms on his website, a potential customer goes to his site, enters in their own information (organization, address, contact info, etc.), can preview how the booklet will look, then purchase the booklet with the customer's info automatically inputted and download. Is this something JotForm can do? Or any plugin?

If I understood correctly you need a payment form that can be embedded to your client's website. That is possible with JotForm.

The following guides can help you to create a payment form:

Setting Up Your First Order Form

User Guide

How to Create Your First Web Form

To embed a form, please check this guide.

Which Form Embed Code Should I Use

When a form is submitted, your client can receive an email with submitted data. It is also possible to attach a submission PDF report to the Email Notification.

Setting up Email Notifications

How to include submissions as PDF attachment in the email notifications?

Submitted data can also be downloaded from the submissions page. 

How to Download Form Submissions as Excel/CSV/PDF

No, this is not what I'm looking for. I'm looking for something like Vistaprint or online printing. I go to a product, enter in my information, preview what that information looks like on the template, add it to my cart, then purchase and download. In this case, the "product" is a form - like an informational booklet. We want the customer to look at the booklet, enter in their information, preview the booklet with their information in it, then add it to a cart and purchase it. Then the booklet (without watermarks or whatever) is digitally sent to them and they can download and print. Is this something that JotForm can do? If we convert his booklet info to a template within JotForm?

I'm afraid we do not have an option to create booklets with watermarks. What I could suggest to consider is creating a template using TEXT element. It provides an option of rich text editor and allows to include form fields within the text: