I work at Home Depot .... yes you got it in Plumbing.
I work in an area where people come on Vac. so many come in with a leaking drain or a water line that is in need of repair.
I tell them if you can rip all the plumbing out and put in the type you have in your house.
There is nothing worse then coming into a town on the "weekend" in any type of RV and finding a leak and the RV store is closed on you guessed it the "weekends" or has short hours.
Most hardware stores are open sat. closing at 5 or 5:30 and big chain stores are only closed 2 times a year and open to the late hours. But what they offer is plumbing for the house few do the RV's.

So when you are doing that Plumbing project or inventing a new way to heat your water .... when it breaks where will you find parts. Look in the plumbing department of any store and you will see what I mean.
I have helped many an RVer Jerry Rig at drain or water pipe because the RV store was not open or a long ways away.
And if you use compression parts make sure you see them in more then one store Cause when it goes it may take several parts at $5 or more each.

Ron Dickey
Los Osos, ca