The saying over here is that rental cars 'go faster, stop quicker and beat everybody from the traffic lights.' My friend used to hire cars and race them ...

A former ex-rental car might be OK if it's a type that's not rented often, like the small cars. Most people seem to rent mid to large cars, which will have the greatest wear and tear.

Checking out ex-company cars may be useful. I'm not sure about your taxation laws, but most companies here lease cars for their executives for three years and then sell them via a dealer or auction at a big discount. Some are abused, but most are kept in tip-top shape.

Good luck. I put buying a car in the same category as buying swimsuits and jeans ...