Robotics cost $800+, but require no plumbing at all (in other words, no pressure lines and no booster pump) -- they are plugged into an outlet and are completely self-contained. They have microprocessor "robotic" logic to clean your entire pool, and have their own self-contained filter bag that is supposed to filter out very fine material. I don't own one so I can't vouch for one, though the people who own them on this board speak very highly for them. Dolphin and Aquabot are 2 of the more popular brands. Check out the Pool Cleaning section of this site for lots of posts and opinions about them.