Process of buying a used car (private dealer)?

Assuming you're in America, most of what you need is on the title such as vin number, price and sellers release of interest, signatures etc. But you may want to also have them fill out a separate bill of sale. You don't need to go to the DMV, take your paperwork to a local licensing agency and they'll take car of the transfer and give you tabs if you need them... you'll get your title in the mail a few weeks later.