I'll just add that none of this is new information or regulation. Some counties or municipalities have some varience but generally you cannot cater from a home kitchen...some exceptions probably exist for cookies, cakes, etc. but if you handle raw meat and other hazardous foods you must work from a certified kitchen.
Now, this can be a church kitchen or school cafeteria (private schools are good choices) assuming they are compliant with local and/or state licensing.
Yeah, it sucks...but that's the way it is. I'm fortunate to have a church kitchen (inspected) to use and this works out well since most of my catering is for the church (and my previous church). My previous church had a school and child care facility and so the kitchen was fully licensed. My current church is "church kitchen" certified...but that will probably be changing soon to fully certified.
Even if you have a spiffy concession or catering trailer with sinks, etc. you STILL need a commissary (certified) for cleanup, potable water, grey water drainage, etc. You also need a covered area with "durable" suface (ie. cement, asphalt, etc.) area for cleaning the rig.
Nobody said catering was easy!!!
My perspective is from Florida and specifically Pinellas County. Other areas will differ, but not much.
Southern Brethren BBQ Competition Team
"It's all about getting paid!" - Myron Mixon
"I love being hated in my hometown!" - David Hair
KingFisher Gator Rotisserie cooker, WSM, Stainless 5 burner with IR gas grill, Turkey Fryer, Weber JD Commemorative grill, slightly used Bandera chamber for future use as a cold smoker, Masterbuilt 40" insulated ELECTRIC smoker