I am up in Minneapolis and just starting also. I would first start with Pyle's suggestion. Talk to the county HD. Are you in Rochester?
It is weird up here, because my kitchen is licensed in Minneapolis. If I do a graduation, wedding, etc. at a clients home in Minneapolis; smoker must be NSF. If I cook at a party anywhere else in Hennepin county; I could use anything.
I know that isn't what you asked, just showing how different requirements can be depending on where you prep and where you cook.
Network with some BBQ joints in your area and see if one has a helpful resource at the HD.
Keep us posted on your progress. I will IM my number. Post some pics of your rig; always love pics of trailers.
2 - WSM 18.5, 1 - WSM 22.5, and 1 - ECB Smoke n Pit.