The floor in the trailer needed to be totally replaced. I choose to use a 3/4 inch plywood instead of the sound board and plywood. Getting the old floor out was not all that bad. All the bolts holding the floor to the frame were rusted so I had to cut them off from underneath the trailer. I used a sawzall for that. The larger twisty type nails holding the floor down from the inside were much harder to get out. Once we got the floor out, I reinforced the areas in front of the sink and also in the entry. I cut 2 x 4 down to the proper size 2 x 3 to match the ones they used and screwed them in.
We sealed the plywood with a white primer sealer first. The 3/4 plywood is about an 1/8 of an inch thicker than the original combination of the plywood and sound board. So getting it under the cabinet next to the door, I had to trim the bottom of the cabinet with the multi tool. I just put the plywood up to it marked the difference in height and cut it off. It slide under it with just a little pushing. Im sure I could have just removed the cabinet and then put it down but I didn’t want to remove it because it helps support the siding some. Once I get some of the framing replaced and reattached to the main frame of the trailer Im going to remove that cabinet and do the repairs and refinishing needed.