Custom Check Out Option?

Hi Everyone

I was wondering if someone could help me create a way to customize how my customers check out. Here is what I would like to do:

When a customer adds an item or items to the cart and go to check out, I would like for them to fill out the shipping and billing information, but no payment information. Then when they click the Purchase button, it will send me the cart information, where I can then send them an invoice with the correct shipping information and so forth.

I would also like to change the Purchase button to say “Submit Request”.

My website is http://chemedesigns.com

Any help is greatly appreciated! Thanks!