I am looking to buy endless pool model R200 12'x7.5'x50", I have split level house and low level is 3' below a ground level. I want put a new pool on the same level, 3' below ground. Thinking to put 12'x16' four season sunroom around the pool. My question is how much room around the pool will be enough to have access to all parts? Will be 16'x12' sunroom adequate for this pool ? Does anybody have experience to use tankless natural gas boiler plus heat heat exchanger ? Any advice to lower construction/maintenance cost will be greatly appreciated.Thank you.