Sounds like it might be worth getting a rental car instead of dealing with his manipulative BS. It sound like he's either trying to make you mad about it so he can play victim to try to make your GF mad with you or make it financially difficult for you to date her.

I'd immediately give him back his car and rent a 2017 car.

Replace your car and give his back. It might be that is the best he has. And watch out, daughters are often have the same values as their dad.

Send him a bill for the stuff you fixed/replaced. His car, his responsibility. Unless you actually broke something, you only have to pay for filling up the car with gas if you're borrowing one.

To be fair you are fucking the ass out of his daughter

Then take it back duh

Why are u paying??

You are choosing to replace these items. You could just return the car.

Don't pay for his car's repairs. That's his responsibility. You'd be better off renting a car temporarily or learning the bus/train schedule. Maybe ask your coworkers if they'd be willing to give you rides in exchange for gas money?

Soooooo when you're done with the car, I think it's totally your right to keep the items you supply during your time of use and then return it the way you got it, just with the gas-tank at the level you found it. Then sell the parts you had to buy if they won't be of any use to your own car. I mean, it might've been a kindness in a way, but if it's a dump, maybe you don't have any obligation to fix it, especially if you'll be needing to get a new car.