I've been looking at lot of 2000-01 Subaru RS and Im wondering if there is any reason why the majority of the owners a re choosing to sell them around 80k miles. l know about the head gasket problem appears around that time and l know that the value drops some what when it hits 100k. Is there any other reason why owners choose to sell around that time?

they probably have the piss beat out of them

Same reason l traded my old WRX at about 100,000 miles. l was going to have to change the timing belt, clutch, and it needed new tires so l figured put that towards a own payment and just have a new car that l do not have to worry about for another 5 years.

As mentioned, that is about normal mileage for an average driven car that old, & it is common for that model of car to have lost its ''new'' or ''current'' feel & those people r wanting to step up in newness. As far as HG issues, when u test drive one, drive it for a longer trip around town than just the typical around the block test drive. Have it running for awhile & watch to see if the temp gauge rises above the halfway mark. Most Subes stay locked at just below halfway on their temp gauges all the time. If from a dealer, ask specifically ''Has this car ever had any known HG issues?'' If they lie & u find out otherwise shortly after purchase, then they r liable for repair--if u can prove they knew.

Most of them have a 100,000 mile warranty.Subaru is are good cars all around.mine has over 270,000 miles and is still going.

About three years ago we bought a 98 Subaru limited ed. with 100k miles on it. It was squeaky clean when we bought it, really really nice inside & out. We started having problems almost imediatly. We had to replace the head gasket & then the transmission & there is this super annoying vibration that has been going for almost the entire time we've had it. Also the car alarm is on the same frequency as Dodge & some Chevys so the car goes off all of the time. l can leave the car unlocked & come back & it is locked & l never touched it. l really want to say l love the car, maybe it was even a good car at some point but honestly it is been horrible. We r almost finished paying for it & plan to replace it as soon as we can & hopefully will not have to put any more money into it.

It is not just Subaru's. The majority of vehicle owners begin looking elsewhere around 80k. The main reason for that is the vehicle is usually paid off & the warranty has expired. Also, the majority of people do not maintain their vehicle the way they should, & poorly maintained cars grow problems after 80k. For peace of mind & laziness people sell a car in fear of work.
l have had mine for 4+ years & going over 108k without any problems & l drive it hard. A $300 timing belt is better than 6 years of interest on a car loan.