First, welcome to the forum !!! We're happy to invite you into the "trailer owner's club"... You'll soon find that there's as much "work to trailer ownership" as there is "enjoyment in owning a trailer"....
If your trailer has "sat unused" in a parking lot or in a field for most of its life, it may have "suffered from lack of maintenance" ....
One of your very first "projects" should be to get on the roof and carefully inspect EVERY seam, crack, projection on the roof, clean them and reseal any area that even looks like it might be a source for water intrusion. Use soap and water (Dawn and a nylon scrub brush work great) to clean the roof and all that sealant that appears "gooped all over things".... Look for any separation of the sealant, any suspicious black or green molding areas and "feel for soft spots" under the TPO membrane. Those are "key findings" that show a need for further work in those areas.
Then, even though the tires "look new" they are likely to be "dry rotted beyond use"... Look at the manufacture date on the tires and replace if they are older than about 5 years. Don't forget that if the trailer has been sitting for some time, not only will the tires suffer from "flat spots and water damage" but so will the brakes and the interior surface of the wheel hubs. Also the wheel bearings and grease seals are likely to be "far beyond their service life" if they've not been properly maintained.....
Then, on to those rubber coated propane lines, the service date on the propane tanks and any other rubber or vinyl item on the trailer. Things like plastic hatch covers, refrigerator vents, vinyl screw cover strips on the aluminum molding all need to be checked for serviceability and replaced if needed....
Then, inside, if the trailer has been "in an open field" you may find evidence of mice infestation such as droppings in the drawers, under furniture, in the back of cabinet spaces, etc. Lift the mattress and look for mold/mildew under it. Do the same for any furniture that sits close to the exterior walls. Condensation forms in those "closed spaces" and can lead to problems in those places.
I know this probably comes across more as a "your work has not even begun" rather than a "have a happy weekend with your new trailer"... But, the sooner you get everything inspected, cleaned and working properly, the longer your trailer will last, now that it's no longer an empty shell but is doing what it was intended to do, bring smiles and happy days to its new owner....
Enjoy your new to you home away from home.....
