If you ever do a factory tour and see how they make trailers, step #1 is to build the wood platform on top of the steel frame, step #2 is to roll out the vinyl and staple it down. Walls (interior and exterior), all cabinets, and carpeting (where it's used) are all put down on top of the vinyl.
The original sheet vinyl held up for many years, but then we got one of those "arctic blasts" with sub-zero temps, and that winter the vinyl ripped about 3' long right in the middle of the floor.
Our first replacement floor was vinyl planks with the overlapping self-adhesive edges. The box says 25-year warranty, and when you open the box, there is a piece of paper on top that says in big letters, "Warranty void if installed in an RV." Out of all the reviews I could find here and elsewhere, about 90% of the folks said don't use this stuff, about 10% said they had no issues. We rolled the dice, then had another "arctic blast" roll into Louisville with sub-zero temps and by the spring all the joints had separated.
Replacement for that was the new click-lok vinyl planks that have an edge locking mechanism like laminate, but at a fraction of the thickness. We didn't want to build up the floor too much and create clearance issues for the slide.
That floor help up well for several years until we sold the trailer.
As far as installation, I cut out the vinyl along the cabinets, installed the new floor with 1/4" expansion gap at all the edges, then used shoe molding stained to match the cabinets to cover the gap, just like you would do at home.
