haven't seen anyone posting doing same thing I did ---
I now have sand in the coop (roughly 4 x 4 x 4 with roosts across the middle each way)
previous owner of the coop had left the plywood bare, put down a double layer of heavy black plastic, and used deep hay
despite the deep hay, his chickens had scratched multiple holes in the plastic
I cleaned everything out, sprayed it all with diluted bleach ---
then after it dried, painted the whole thing with offwhite glossy exterior latex paint
then the sand went in (builders sand) ... about two inches deep
(several people expressed concern about dampness through sand --- if the underlying wood is painted = not a problem;
and paint is a whole lot cheaper than vinyl flooring, if you buy vinyl new retail, especially if you also ask at the store for any returned mis-mixed paint !)
it is very easy to rake (child's metal lawn rake) and scoop --- once I figure out where the chicks want to roost, I will put a poop board under the roost they prefer, then will have very little to scoop up
to keep the sand from tracking all over out in the run, I put a couple of rubber nubby Welcome mats just inside and outside the poop door -- got that idea from mats sold to keep kitty litter from getting tracked all over the house
(the run is big clumps of weedy grass -- when they eat the grass down to buzz cut length, I pull up more from the yard and transplant it in -- and they have a couple of corners with several inches of sand to bathe in)
also put a nubby mat under the waterer, so the chicks' feet get cleaned off before they drink
standard chick waterer kept getting knocked over, so I borrowed DS's gallon-size automatic dog waterer, which they haven't managed to overturn yet .... his dog prefers water in a great big stainless bowl anyway