I honestly can't recommend buying a former rental car at almost any price. At best they are neglected and worst they get beat on with no mercy. Or so I have heard.
i see where you are coming from but i dont understand how you could beat the hell out of it and the rental car place not know or see or feel that some thing is wrong with it. I also dont think people who rented it drive it like i do. Im sure 80% of the people at least were mature non car people would needed it for business or to get around, not some kids doing burnouts. But then again even if they sat there and did burnouts and floored it everywhere, so do I and my car is problem free up to 60,XXX. I think its more of a mental thing that an actual problem with the car. Its a mustang, they are meant to ride hard.