You have to really scour the internet, KSL, ATVtrader, craigslist, etc...
I live in southern NV and am driving to CA today to buy a 2018 Polaris RZR S4 900 EPS Black Pearl with a little over 1,000 miles on it for $12,500 which also includes a 2 place trailer. The guy bought it for his wife and 2 kids. The guy/dad loves riding his dirt bike and the wife wanted to go with him. Well, the kids are 2 and 6 and after driving it about 8 times the wife wasn't having any fun, imagine that.... So, he is just trying to get rid of it at this point. I have been looking every night for quite a while, had a strict budget, wanted a machine that had less than 2,000 miles on it, was FAMILY friendly (not a 150 HP screaming machine) and knew what I wanted. I think it's important to have a dealership that is near where you live so not if, but when something breaks down you can get it fixed. I also had a list of specific questions to ask the sellers (rollovers/accidents, maintenance records, and type of riding such as dunes or trails, etc) I have to admit I came across as almost annoying but I feel you have to be thorough because as another poster in this thread mentioned people beat up these machines and then try to sell them after a few years for nearly as much as they paid in the first place. Lastly, I was leary of aftermarket parts and "upgrades" as oftentimes that means my buddy and I jimmy-rigged the motor or made it sound "cooler". Anyway, sorry to go on and on but it took me several months to find what I was looking for. There are some deals to be had but I think the side by side market is really crazy right now and it takes patience, some digging, and a little bit of luck. Good Luck!