There is a product out there, its called RV Locate. We have one, it took my husband less than 5 minutes to put it on. It runs off of 12v when the tow vehicle is hooked up - but it also has an internal battery
that holds a charge for up to 6 months in storage. The tow vehicle charges the internal battery
It's the only one out there that we found that the device battery
will last, is maintenance free, has a warranty, is waterproof, notify you via text message of motion / geofences, etc. And, its only $10 a month. No contracts.
We got ours on a promo from a dealer, so we paid $199 for it. The coupon code was CASTLECOUNTRY on their website.
We love it, best of luck!
RV Tracking Device