Create a "Quote Builder"

First create all of the products you want to feature on the form.

Here's the article that walks you through how to create products.

Next, add a purchase element to the form.

Click the "Sell Products" dropdown in the top left and change it to "Give Quote".

Add all of your available products to the form, with all the options so you can do everything from one form.

You will notice that the credit card element completely disappears, however you'll want to add in their first and last name and email at the very least so you can follow up on the quote.

Depending on how you use this form, either you or your customers will be able to select different products and options based on their requirements.

The best structure is slightly more complex than this, with a "Multi-Step Form", where the contact details are on page 1 and have to be submitted before they can access the quote element.