Create a form to embed to websitebuilder.com website

I am currently building a website on websitebuilder.com. I don't need a Store as such, as it's a subscription site with a one time only check out. What I do need is an interactive form, that new members will complete before entering their payment details. I don't want to pay a form builder as they have ongoing costs, so I just need a form that I can insert in to the website builder (I might need some technical assistant with that too - but it does accept code I believe). The form I want is interactive - the first three options are three images - the user selects one image and then the second option pops up with three further images, and so on. After that, the user must select their sizing, and then enter their contact details. I can draw a mock up on the form for the designer. The concept is very similiar to the sign up process on [login to view URL], or on [login to view URL] when you select what phone/plan/GB size etc. I need the submit button to either export in to a CSV file (can this be continually populated by all form users?) or simply sent as an email to me with their selections under the headings. The SUBMIT button will also then direct them to the payment page.