Much of our work is done in areas with well water. We haven't found the perfect solution - regular and consistent cleaning seems to be the key. Having said that, the clear glass with a coating (such as Endura Shield and there are others) seem to hold up best so far. The glass with the coating would come from one of your local glass suppliers and the door would be custom made. If there is a seat in the shower, or room for a small portable shower seat, then the addition of a grab bar is always a good idea. We also always recommend a hand held if for no other reason, it makes cleaning a shower much, much easier.

Houzz posted a great article about cleaning shower enclosures recently. Check it out: https://www.houzz.com/magazine/get-glass-windows-and-doors-gleaming-clean-stsetivw-vs~2239417