Down in this basement I can see 2 layers of gray floor paint were it's
peeled or scraped off the concrete floor over many years. Just a couple
weeks ago the whole place flooded and was underwater for a couple days.
Would the water absorbed into the concrete have done any damage to how
well the bottom coat sticks to the concrete? I'm guessing if it was
done right the first time it should be ok?

Now if we want to repaint the floor again, what kind of prep work should
be done? I know any loose or peeling paint should be removed, but how
do people do this on a large scale. Is there any kind of equipment to
rent? I thought of a sander for wood floors but imagine it would get
clogged up with paint fast?

The bottom line is we want to paint it and do as good a job as we can.
Possibly garage floor 2 part epoxy paint... if that can go over the old
paint, I haven't checked the labels yet.

Idea's?