Looking at one camper with unducted A/C

Never owned a trailer but can't be much different than motorhome. I've had four and the current one has ducted AC. Ducted will distribute the air more evenly. I never had a problem with the non ducted units. Either one will have a hard time cooling down a unit that has been out in the sun all day with no AC going. Trees are your best friend for keeping your trailer cool.

Others have added a second unit and wired separately. Sounds like a plan.