How to politely disallow my grandpa from driving my car(s)?
Sorry if this is too long but my grandpa has an old car and it's air conditioning recently broke (mind you he had 2 cars and decided to sell the newer/low mileage/much more reliable car to keep this car which air conditioning just failed). As a result he now asks me to drive one of my cars so he can go to his Doctor appointments in this hot summer. I have a sports car and an old hybrid, he initially insisted he drives my sports car since he knows I commute on weekdays driving the old hybrid (not happening). Not wanting to sound like an asshole, I told him he can take the hybrid as I will just take the sports car this workday. He takes the hybrid at around 11am for his Doctor appointment and doesn't come back until 8pm with a shitton of groceries. The thing that really irritates me is that he has a habit of destroying everything that he touches. When he comes back, the tires hit a curb because he didn't bother to slow down fast enough. I immediately notice the alignment is not the same. On top of this, I also immediately notice the driver door is super loose and not as firm when opening/closing as it was before (I watched the camera and he literally folded the door outward while trying to get out, he is a huge guy). He greeted me in the evening saying that he bought insurance for a year which covers my hybrid that he just drove and mentioned how he plans on taking it again this week for another doctors appointment. How do I nope out of this without sounding like an asshole?