HELP !!!!! can anyone do a trailor floor crasher show please

floors are floors, nothing magic about it.

if the whole thing is going, you need to take the fittings and fixtures out of the kitchen and bath, pull up the old stuff, and replace it. except there is water exposure below, so I'd chase the Internet and see if best practices include putting down a waterproof layer first, then laying subfloor, then correct prep for the final floor in each room, and then the final floor.

then you replace the cabinets, dishwasher, toilet and tub etc.

this is esoteric enough that I doubt anybody is going to do a "trailer crashers" show. you're on your own. I'd consider an aluminum plate bottom to the floor myself, with suitable plastic between any iron framing members, and plastic isolating any plumbing metal from any other metal, say spec-60 drain line siliconed into place.

again, you need to research best practices. this is a major job, and since it is Structure, may need permits and all that truck.

No offence meant to the other poster but it's no where near as involved as suggested.
It's a very common thing for bathroom floors to fail in reguler homes and expecially true in mobil homes.
The most common reason I've found is most often they use a partical board subfloor. It gets wet even one time and it turns to oatmeal.
Working on a floor in a mobil home is no differant then a reguler house, it gets removed and replaced the same way.
There is not need for the metal and all the extra stuff suggested.
Remove the toilet, vanity, baseboards, door trim on the bathroom side, and bathroom door.
It's best to cut out the old floor with what's called a Toe Kick saw (Home Depot can rent you one) It will cut right up next to the walls and tub.
The inside corners can be cut out with a Sawsall with a short blade or an ossilating saw.
I then cut the floor into about 2' sections with a ciruler saw set to 3/4" depth so the sections can be removed easyer, or if you know where the floor joist are you can just cut between them.
Once it's all out, clean up the floor joist if there's glue on them and use Advantec 3/4" T & G subflooring with constrution adhesive on top of the floor joist using ceramic coated decking screws.
If the plan is to go with sheet linolium the next step is to lay 1/4 underlayment rated plywood (not louon) making sure the seams do not line up with the seams in the subfloor.
I use a pneumatic narrow crown staple gun with 1" staples to attach it (no glue under it) It needs to be attach every 4" on the edges and 6 to 8" in the field. Use floor leveler to fill the gaps and any flaws.
Now your ready for the new flooring.