Obviously, I had all of the tools, etc. I bought a 120 sq foot area for $130 shipped. The amount of soundproofing material to do the rear area was about $30. Each door was about $15. I probably should have added a little more, so $20.
I just wish I had bought raammat since it's much better. If you don't care about very good results, the ebay stuff is fine. But for the labor, why not spend an extra $100 and get stuff that is really good?