I have read that most are using plastic as temporary walls. I wanted something on a more permante basis. I have to put something up as the walls are exposed. So what do I use (dry wall, MDF, Etc...) I have everything ready to go just waiting to set up booth. Also are furnace filters from home depot good enough filters and which brand or model furnace filter should I be looking for. If not furnace filters what other low budget filters do I get. Thanks a million!