Purchasing a car from a private seller. Nightmare.

I would take it to a reputable shop and see what is the problem. That would be my first task.

If this guy sells X number of cars annually most states require him to have a dealers license. And thus the title is handles per dealer requirements, which is NOT jump title. He may not have to send it into the tae for immediate transfer, he simply fills out the title as required and state gets correct taxes. State getting taxes is what they want.

Private individuals that are not going to keep or drive , insure said car, many times do not pay tax and transfer it into their names. Not legal but....