Need inspection. Who should pay is up to negotiation, but as a buyer, I won't pay him any money for inspection. If inspection fails, do I get my money back? If seller decides not to sell the car after inspection, do I get my money back?
It's not a big amount of money, but there is a hassle to make appointment and spend time to send the car for the inspection.

Need to buy insurance. Need to agree who pays the transfer fee.

Need to ensure the car can be transferred - no outstanding loans, etc.

You are scared the owner will run away once he gets your money. He will also be worried that you don't pay him after transferring name. Dilemma... No wonder used car dealers can still survive in this internet age.