Nothing wrong with a 20 year old car as long as someone cared for it and maintained it properly.
You do not want a 20 year old money pit that someone neglected and "postponed" every repair on. If you get a money pit, you'll end up sinking thousands into getting everything correct. I have committed to a vehicle and I have done this before, I sank about 5 thousand into something I bought, but I liked the car and it was in excellent shape, so whatever.
Make sure the vehicle has zero leaks, engine and trans are good, power steering and A/C are good, struts are good and not leaking, steering rack and tie rods, cooling system, etc etc. Basically ALL major mechanical systems are functional and not falling apart and not leaking.
If you start with a good solid car, you won't have too much to deal with, and when you do have something more major, you can plan ahead (i.e. your mechanic lets you know that he is noticing a strut begin to leak, now you start planning ahead to do all four struts but it is not urgent and can be done any time in the next year or two, etc)
I have bought a few money pits and went nuts trying to keep up with it. I don't like to do that anymore ......
