I believe it is safe to state that Roadtrek used PEX in the plumbing.
In my limited experience working with PEX, I just love using "Sharkbite" fittings. If I had a leak in a PEX line I would just purchase a 1/2" Sharkbite coupling, cost about $8 and cut the existing PEX water line at the leak and snap the Sharkbite coupling on since the only tool you would need is a small saw. It is that easy - I have never had a leak using 1/2" PEX tubing. The PEX water line doesn't even need to be dry, but you must cut the existing line smooth and straight before applying the coupling.