When we first set up shop for End To End Training we knew we wanted both a flip chart and a dry erase board. For the latter we did some research and many people recommended tileboard, available from the local home supply type store for about $10 for a 4'x8' sheet, a lot cheaper than the store bought ones. We put a wood frame around it (using pocket hole joinery if you're interested) and used it for 18 months. It worked reasonably well, but the dry erase part turned out to be more like almost dry erase. We had to use a sponge that was barely wet to get stuff off and we also had a couple incidents where permanent markers got used. Dry erase is supposed to be easy!
We just moved to our new office and debated just replacing the tileboard (and making it easier to replace again in the future), or trying Plan B - plexiglass. We purchased a 4'x8' sheet of 1/8" plexiglass for $100 and mounted it on top of a new $10 piece of tileboard, then secured it using screws and fender washers. Installation was a pain, lots of static electricity between the two sheets and as we drilled the mounting holes we kept getting bits of dust sticking to the inside which we then had to carefully wipe away trying not to leave fingerprints and other smudges. The plexiglass also doesn't like to quite lay flat. Close, but not perfect. A mounting issue I'm sure, but it didn't make it easy! We're testing it live this week in class and it erases easily with a soft cloth. Some colors work better than others, we've had to set aside the brown markers for now (maybe because they are the low odor ones), and it's just a little shinier than we'd like, maybe should have just painted behind it rather than use the tileboard. We'll see if it works out to be worth the extra money/effort, or if we need Plan C.
If you've found this mildly interesting you might also want to read an article I posted years ago, White Board, Flip Chart, or Notepad?