APT wrote:
so we can keep things charged on the way
What are you charging? Cell phones and tablets for example only need 5V USB, so something like this adapter and your favorite USB cables is a cleaner solution. Seem silly to convert 12V DC (car or RV house battery) 110V or 220V AC just to get it back down to 5V DC.
Laptops can be a little trickier, but there are DC->DC adapters available for most.
That was my guess too. I believe you want to charge your devices, cell phone, tablet etc., if so, just use any 12 volt receptacle & appropriate device adapter in the coach & forget about the inverter. You need to have the rental service explain the power distribution system in the RV to you before departing for the trip.
