I bought a HF tire inflator (12 volt) a couple of years ago. Looked really nice and purdy on the shelf and was only around $10. Wanted one for our RV tires to top them up as needed. Didn't work at all, no way, no how. Ended up leaving it in a clubhouse at a campground for some other sucker... Now I know a lot more about 12 volt inflators.
A pancake compressor works fine for car and pickup tires. If you were to do a lot of it, maybe you could use a little inline air dryer and oil/water separator. These things make an annoyingly loud sound tho. (to me anyway).
There's lots of tire inflators out there, but many of them are really slooow and you should look at the specs closely. Buyer beware. If you wanted a 12 volt portable, Viair makes nice ones.