I've got one of these cheezy little vacs:
http://www.amazon.com/Shift3-12V-Canister-Outdoor-Vacuum/dp/B002AKF9W2
Got it years ago - it was on the clearance rack at the auto parts store. I think paid 10 bucks or some such for it. It works okay. Not great though - it's underpowered. Amazingly, it's like...I dunno...7 or 8 years old and still works.
I wouldn't recommend it. It was worth the 10 bucks, but I'd really like to have something with more power.
Kinda had my eye on one of the American made MetroVac units. I think they actually invented the hand vac back in the 50's. They make a 120vac unit with a 500w (!) motor, and a 12vdc unit with a 130w motor. That's a pretty punchy motor:
https://www.metrovacworld.com/Metro...erformance_Stainless_Hand_Vac_AM-6BS/overview
A lot of places that sell it online, screw up and say the 12v unit has a 500w motor, which is patently stupid - that would be over 40 amps and a cig lighter is usually only rated for 10 or 15 amps. Even Amazon does it:
http://www.amazon.com/Metro-AM6BS-S...itan+Hi+Performance+Stainless+Hand+Vac+AM-6BS
See where it says, "500 watts of power with a new state of the art fan enclosed motor (12 Volt, 11 Amps)"?
Well, 12 volts x 11 amps does not equal 500 watts. The 12v unit has a 130w motor.
For a trailer with a dust problem, you'd probably be better off with the one that is a blower as well as a vacuum:
https://www.metrovacworld.com/Metro...erformance_Hand_Vac_Blower_AM-12_IDA/overview
My only gripes are, A) not wet/dry, and B) takes a replaceable bag.
If they made a 12v wet/dry vac with no special bag required, I'd buy it in a heartbeat.
Hell, I'll probably end up one of these days buying one anyway - just because they are ************.