The greatest concern for reliability is the owner. However you have excellent info already -- you have a service history of sorts, and you also have the owner's assurance that it hasn't been abused and that the owner drives like a grandma.Then on top of that, what are some common issues that I might see with this car?
Therefore, the owner abused the car.
This varies depending on what was wrong initially and whether only what's wrong is fixed or if there is "while it's apart" syndrome that leads to more things being done. It can vary from a quick once-over the block and new gaskets (not really a rebuild but then again what is reality these days) to big ends, pistons, rings, valve job, polishing etc. Depends.Lastly out of curiosity, I am wondering what an engine rebuild does,
Nobody knows.and how much longer the car can go on average.
The motor should not have failed in the first place. 60K is a "new" motor.
Most common fault is the owner. Then it's unauthorized or imitation parts that cause trouble. See the how-to-buy threads in the purchasing forum for things that you should check (on another car, not this one if it were my time and money).