Wash, Rinse and Sanitize...How on site?

I have a polycarbonate prep table on my trailer rig. I usually have a large roll of butcher paper with me that I cover it with when I'm using it for seasoning ribs or whatever. When finished I throw the paper away and wipe the table down with those Clorox kitchen wipes that contain bleach. Pretty much sanatizes it. They also work great for hand cleaning.

I never cut or slice on the prep table itself but always use a cutting board.

I usually set up a couple 4 foot folding tables around my work station for other purposes and those I spray down with the Clorox kitchen spray and wipe down.

I generally have my portable steam table on site with me. This also works great as a hot water source. Mine has a garden faucet mounted underneath for draining. I can drain out a quart of hot water and add a little dish soap if I need to clean up a pan or wipe things down.

You could always add sinks/faucets to your rig. A on demand water heater would work if you need hot water. I have also seen guys use a rv propane 6 gallon hot water heater mounted on their rigs.  If you need to get it NSF approved check with your local health department as to their requirements.