Dennis,
Yeck, I have replaced the whole floor in the front bath and added a new tub and toilet. All the kitchen floor, including under the pantry and ice box. The back entry floor, including under the washer and dryer and the floor between the back entry and around to the kitchen. I have replaced half of my bedroom's floor too.
Dang wafer board. Any moisture near it and it expands and weakens enough to put a foot through it. Most of the moisture came from condensation from the under floor A/C duck. Front bathroom floor replacement is being charged to my son falling asleep in the tub with the water running. Add in a overflowing toilet or two and a tub drain that starts leaking.... Well, you get the idea this is not my first rodeo in R&R floors.
I do have knee pads. I have wore a few pair of knee pads out over the years. It's not the knees so much, but hours of kneeing and reaching below your knees. This has me stop every now and then and stretch my back straight.
Floor R&R is cheap. It is that $400 dollar garden tub I am replacing that hurts me the most. I found $285 tubs online, but they charge $100 for delivery. I can pick the thing up myself, it is so lite. But it is 54 x 40 inches and 18 inches tall. The worst part is not being able to take baths, just showers until I get finished. I like to soak in hot water after working in weird positions day after day.
On the other hand, all this DIY has bought me a lot of fun toys to work with over the years. Pneumatic framing gun and pneumatic stapler and brad nailer.
Only way I am getting to use the tractor is it park out over the back deck so I can throw more junk floor into the bucket.
hugs, Brandi