I agree with phila_guy about the white tile board from Home Depot.
I originally bought a 4'x8' sheet of clear plexiglass and used it for awhile until I too discovered the Zackarias site. The plexiglass is expensive and cumbersome to move. The HD white tileboard is cheap and a lot easier to move around. If it gets beat up from use it is easily replaced.
The white tile board works well with white seamless paper, it may not work as well if your backdrop is not white. You could also use the tile board to make a gigundo reflector too.
I have two sheets of the tile board and slightly overlap them by about 1/2" with the one closest to the camera on top. The seam is practically invisible and easily Photo Shopped if necessary. I am planning to add a third board to give me more reflective area in front of the subject. Getting the lighting even on that might be a project though.
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Bob
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