Had one once. It cost more to heat the pool in the summer than to heat the house in the winter. And we didn't get the water very warm, either. Cleaning it was a nuisance. One winter, next door's dog got in the pool, fell under the ice and drowned. All the neighbours' children used to turn up on sunny days in their bathing costumes saying their parents were out so we had to let them stay and swim. Trouble was, they couldn't swim and had to keep getting rescued. Much Much more bother than it was worth.