I'm not a vendor but insurance also comes to mind as really important.
As far as vending... it would seem that unless you had a very low cost meat provider direct from the source, a Restaurant Depot or general food distributor like a Sysco would be the most common if you're buying in relatively low qty... or maybe a local meat wholesaler if you've got decent volume.
22" WSM & Kettle
Former owner: Jambo, Klose BYC, Med. Spicewine, Pitts & Spitts, XL & (2) Med. BGE's, (2) 18" WSM's