I recently spoke with two FSBO property owners and one owns his property free and clear. If I want to make a formal offer and ask for seller financing do I use the traditional purchase and sale agreement or do I need an attorney to draft specific paperwork with my term? I want to present my offer ASAP before anyone else has a chance to close the deal.

Yes, you can use a standard purchase and sales agreement 

@April Choi Thanks! I wasn't totally sure. I'm used to making offers through a real estate agent. I appreciate the feedback.