Has anyone had to do this? My pool was built with only floor returns, so the circulation is terrible (okay, nonexistent). I have a couple of areas where I can easily access the backside of the shell and have plumbing close by. I'd like to add 3-4 wall returns. It's a free-form pool with lots of ins and outs, so I think it would take that many to really get the water moving and into the skimmer (which was put on the wrong end of the pool if you ask me). I know that costs vary quite a bit by region, but I'm just curious. More than likely I'll end up doing this when I replaster-- hopefully that will be next year if I can save up some money.