Here is my general feeling towards miles / age for my own situation. Note this is based on my experience, and I do not have data to back it up:
- All miles are not equal. Highway miles are generally preferable to city miles. The expensive parts (engine, trans, etc.) tend to wear out more from starts / stops, heat cycles, etc. I'd take a 2012 car with 90k miles (obviously highway) over a 2002 car with 50k miles that had been used for city driving. Tires, suspension parts, etc. generally wear out regardless of how the miles are travelled BUT they are far easier / cheaper to replace than engine / trans stuff.
- Cars have made substantial increases in safety and mpg in the past 4 or 5 years or so. I would tend to lean towards a higher mile newer car over a lower mile older car that had less sophistication (and I don't mean touch panels in the dash board). More speeds in the transmission, direct injection, and now, downsized engines with turbos.
- Simplicity is key (somewhat in conflict with the above). Complicated cars usually mean complicated (expensive) repairs. I just got rid of a 2005 Volvo S40 T5 with 180k miles. While I took care of it, and it was relatively reliable, I was always terrified that some mystical problem only solvable by a dealer would pop up at an inopportune moment. And it would be expensive to fix. No such fear with my current driver (02 Focus).
- Pick a car that is known for reliability, has a fan base / support, and is common. Parts will tend to be cheaper, or good alternatives to factory parts available. When something goes wrong, it is easier to diagnose. Couple weeks ago my car started running on three cylinders. Limped it to a parking lot, checked which cylinder was misfiring by pulling spark plug wires one at a time while running, found it was #4, looked it up online, and within a few minutes, found that a common failure is the coil pack. Threw in a spare, ordered a new one, fixed for cheap.
So, specific to your choices, it depends on how car handy you are. If you are on the end where you don't / can't do your own oil changes, I would lean away from something with 150k miles or more, even if it is a Toyota. While your commute will go down in frequency (good), the distance isn't, so that is an issue. For these reasons I would probably cross off the one with 200k. The Scion is a hatch, which is infinitely more utilitarian than a sedan (assuming the 01 Corolla is not a wagon), so to me the choice is easy. Cheap, reliable, relatively low miles, basic Toyota design, sounds like a winner.
