checkout and customer forms

hope this is the right place to ask -

1. I have a new site I'm building that needs a HUGE customer info field. Customers are applying for financing.

2. The customers will not be paying for anything upfront - no need for CC processing or info.

3. Want to use Zen because of the fantastic checkout options - the customers will have a large selection of products to choose from and I want them to be able to put them into one cart and checkout at one time, using one customer info form.

4. Zen apparently doesn't have an efficient way of adding forms to the customer info page.

-SO-

My idea is to allow them to set up a simple name / email address customer account, checkout of zencart, and then have it redirect to a sub-domain containing a form for them to fill out all of their info.

Does this make sense? Would you do it differently? Am I missing a Zencart feature that would do this for me? How would i go about setting up the redirect to another page on checkout?

EDIT: oh yeah, thanks for your help!