We are pretty fortunate here. I think I did 5 PC's last year out of 7 contests. One of them, the health department stopped by to do a quick inspection. Gloves, cold storage (cooler), 3 basin sink (buckets), hand wash with catch. My hand wash jug hadn't arrived, but they signed me off on my word that I would have one. The others, we just cooked and served.
Very few of us participating would have had approved vending trailers, but they have different rules for civic organizations and special events like fish fries and BBQ. If I parked on the street corner to vend, they would be writing me up. At contests, they have to issue.