Just a note on this one. Molift now have a four point gantry system that does not need to fix into walls or ceiling It can freestand with four posts tucked into the corners of the room. It wont cause a trip hazard like other 2 footed gantries. The H rail moves inside the frame so it has a good lifting window. One can have a lower cost entry level motor if its an occasional use situation or a larger 350kg motor if its to get more and varied use.
This could easily fit over a pool and the engineering need is minimal