Have a new TT and I haven't been in it a lot because of winter. I went in to get some paper work and saw that my face frame on the side of my Suburban gas range was marked up so I look under the stove...
For sure go over the entire trailer with a fine tooth comb. Regarding plumbing, go over every single water supply line and drain connection ( don't forget the water supply at the back of the commode ), and then recheck them all periodically. You may find with normal use, these joints can become slightly loose again. They did in my trailer.