How to build a paint booth in your garage without pissing off your wife!

[Rhino]

I'm in the process of doing the exact same thing now, other than I built mine 16 foot long to encompass my entire car and pinned a few of the joints to allow me to tear it down as needed. Mine is for sandblasting so I'm not nearly as concerned with air tightness as I was simply recovering the media.

How sturdy is your structure? Mine seems to sag much more than yours does, even though our horizontal spans are similar.