Toto makes a line of commercial valves and fixtures designed for them...I see them now in airports and other places I've traveled. The average homeowner is better served, IMHO, with a good gravity flush toilet. We're not talking commercial here. The average homeowner can't buy from the commercial plumbing supply houses, nor are they home during their normal operating hours unless they take time off from work. You can buy the repair parts from numerous stores for a gravity flush toilet at all sorts of off-hours. Now, if you are going to call a plumber...he'll probably have the parts to fix it.