Welcome to our group - there's always room for one or two more.
First - many OEMs have dispatched notices regarding oiled air filters. What happens is the oil from the filter can blow across the MAF and cause it provide false information. My car came with a similar filter and shortly thereafter it was found in the dumpster.
Try cleaning the MAF with carburetor spray solvent - if you do a search I'm sure you'll find a number of how-to posts.
Listen and check for vacuum leaks while the engine is running. How long has it been since the spark plug were changed? The TPS is another possible culprit as is the temp sensor. You see, being able to change parts is not as important as to be able to determine which need changing.
Most of my workdays now have me toting a dual-channel labscope more than a wrench.
The CD player was good in it's time but has a small buffer and is more prone to 'skipping' than newer models.
The fuel tank pressure is nomal as long as it isn't trying to launch the cap across the street when you remove it.
Only four items cause tires to edge wear - a poor alignment, loose parts that cause a bad alignment, a slipped belt in a tire or under-inflation (which would cause inner and outer edge wear.) Inside wear on both tires is normally indicative of too much toe-in (leading edges wear first.) Negative camber, tilted in at the top, would cause inner edge wear also, but would have accompanying feathering as the tire is trying to become a paper cup rolling on it's side - the inner circumference trying to spin faster than the outer.
Your mother's car may be a touring edition that has a different type speed-sensitive device than yours. That would account for the effort levels. It would appear you need to re-visit the offending garage for the other problems, maybe a big stick would help.
The 'o'-ring could be the noise and vibration issue and you really want the boots corrected before they split and cause the rack seals to go bad.
Good Luck!