They are an amazing amount of fun. But be warned, you will end up down the rabbit hole.
I had springers for years. Cheap ones at first. Then finally bought a nice eihrauch in .177. Really wanted a .22 as well so I was going to get a Benjamin 92. Then I just decided to trade the Weihrauch in at Air Guns of Arizona for a Brocock Sniper XR in .22.
Started with a hand pump. Fast forward 8 months. I have a tank and a compressor. Ended up ordering a nice tank and compressor straight from China. Kind of amazing it was delivered in about 2 weeks.
Anyway the initial outlay is steep, but once you have the stuff it's pennies to shoot. Just like anything else, but once cry once.
They are amazingly accurate. I've taken the time to tune mine and find the pellets it's likes. It likes a range of weights but is definitely most accurate with the 18.13 grainers.
I'd love to get an FX as well, but have no need for 2 $1500+ pellet guns. FX is doing some real innovative stuff.
Check out the air gun forums for used rifles. Many states have a large air gun specific retailer as well.
Good luck with the search.
Oh, and you can shoot them in the backyard! Just get one of the Do All Outdoors Pellet/Rimfire Traps. Or even build your own.