If you search on the internet, you can find some really good deals. I got a 75 GPD with auto shutoff and a pressure tank pretty cheap. In my oppinion, they are fairly easy to hook up. You can buy a faucet diverter, so that there is no permanant changes to your plumbing. Otherwise it will usually require a piercing saddle valve, and a drain valve. I just leave mine hooked up to the faucet, but it only uses water when the bladder tank has room in it. The bladder tank give sufficient pressure for auto top off as well. Works great.