what do you guys think of a 17yr old with a 5.0?

When I bought my 2013 GT I still had my 2005 GT and had it for sale for awhile. Got lots of calls and emails on it but they were mostly idiots trying to trade stuff for it like Harleys or another car etc. Finally this guy called and came to see it and then found out it was for his son who was 17 years old and his first car. I did not feel right selling it to new driver and actually tried to talk him out of it. But he said his son was very mature and trusted him. So I went to start it and the battery was dead. I got out my lithium tiny battery jumper and he swore it would not start it but it did. He went for a test ride and wanted it. Then I discovered the window did not go up that extra inch when you closed the door and the radio would not turn off as well as turn signals would not work all the time. I would not sell a car to anyone that was not working properly and called him back telling him I had to have it looked at. He said OK let me know when you have it fixed. It took me over 2 weeks as my local mechanic could not figure it out and I had to take it to Ford. They did whatever it is they do to refresh the computer and it fixed some things but before I left discovered the turn signals were still doing the same thing. It was the computer that was bad and cost me $600 to replace. Called the guy up and he still wanted it. If it was me I would have walked away at this point but he came and bought it at title transfer place on my home from the Ford garage and gave me a ride home. He texted me a year later asking what oil I used in it and said they have had no issues and his son loved the car. I was happy about that and that his son did not go out and get into trouble as I would have at 17 years old.