Portable air compressors

I always just use the air port available right on my motorhome. I've got a 30 gallon compressor at home, but even at full pressure, it's not that effective on big tires if I want to add 5 pounds plus on all tires. The air pressure available right on board does the best job.

If you don't have on board air, you'll need a tank with pretty high pressure and a large enough available volume.

Pancakes or hotdogs, 120 volt not 12 volt

Porter Cable pancake compressor. For less than a hundred dollars you can beat them.