My stepgrandad had an outside heated one in the late 70s (He was seriously rich!)

He used to clean it himself and it was a peice of piss really. Had a bubble wrap type cover that floated on the top when not in use, so never really got that much shit in it.
Then it the winter he either put a huge heated dome over it (how much would that cost?!) or drain it, then a quick scrub up before refilling for the summer.
It was about quarter the size of an olympic
Rich fooker.... shame ive not seen him for years, could do with some cash lol