I used the white board that you get at home improvement stores to put in walls of showers and kitchen walls etc... the 1/4 inch thick stuff that is gloss white on one side.
As R Fredrick Smith stated you can set your lighting to blow out the seams, or light editing in PS to remove what little shows.
In my old home studio in Tampa I had about 10 various 4 x 8 sheets, in sets of 2 to give me 8' x 8' walls, flooring etc.
A couple of those sets where 12" x 12" tiles glued to plywood so I could change out the flooring at a moments notice etc.
This image was taken using the gloss white sheets both for the floor and wall
This image was the white gloss "wall" and the plywood and tile "flooring"