Most all states have a actual eyes on VIN inspection if you are transferring an out of state title. A DMV rep will actually match the numbers on the title to the numbers on the vehicle. Can really muddy up the water when one state uses the motor number and another the VIN tag number. Another issue is a DMV rep who doesn't know, much less care about antique or classic vehicles. They can make the title process a real nightmare.
My own personal rule is I don't buy any vehicle on a bill of sale or open (signed) title. It's gotta be in the persons name I buy from and we go to the notary together for the signing.
Good luck on your project.