We had a roof failure at the seam where the cap meets the roof on our 2013 3011 DSF. The weak point that caused the failure was fixed in the 2015s so don't worry about that failure on the unit you're looking at. I skipped the dealership angst you read so much about in this forum and took the rig right to the manufacturer even though it meant driving from NC to Indiana to do so. They fixed it up, made it right and fixed or modified multiple items that they had improved on the later rigs. Winnebago won't do that. Thor didn't do that. Heck Newmar won't do that. This company has picked a tough road to go. They are trying to build an economical RV that appeals to the masses with good after service support when they are limited by material costs, independent dealership performance, buyer expectations and production line limitations.
My rig has loose items and I did have a bad post sale dealership experience but that was the dealership. The company and product are good. I just ticked over 10K on the odometer and we didn't have any issues this year other than wear and tear issues. The rig is solid and other than an awning repair and a desire to swap out the stove and microwave for a cooktop, convection microwave and a dishwasher I wouldn't change a thing
My recommendation to you would be to grill your dealer. in the walk through make them go through the rig. Plan on it taking at LEAST a day. Ask for them to...
turn on the fridge on propane to make sure it cools. Check it with a temperature probe to make sure it cooled sufficiently to keep your food cool (40 degrees F). If you have the time, turn it off, open it up, warm it up and then switch it over to electric and see if it cools down again.
scope the holding tanks for debris. You can rent a plumbers camera from Home Depot or Lowes.
Ask them to fill the air bags and record the air pressure they entered.
Ask them to fill the freshwater tank and then run all of the water through all of the plumbing including the shower, sinks and toilet. Find out where that pump is and stare at it to check for leaks. Stick your head under the sinks, around the toilet, in the shower etc to check for leaks.
Turn on the water heater, both the gas and electric
Dump the tanks to check for leaks etc.
Power on the generator and then test all of the devices. You will want to load up the generator so I would also specifically start the AC and then fire up the microwave with a cup of water in it to make sure that the genny stays on and the water heats up.
Play with the cameras and GPS on the unit. Make sure you can go through the menus.
Get up on the roof and walk it. Look for damage, high spots, low spots where the roof joins the walls etc. Look for exposed screw heads that don't have sealant on top of them and ask for them to be sealed with Dicor.
Run the slides in and out multiple times watching and listening for bad noises, jumping, or unusual movements like a slide that tilts moving out or one that fails to open smoothly on both sides. Check on the outside and inside. Get down on your knees and look at the seals to make sure they aren't loose, torn or damaged.
Break out a hose and spray down the entire rig. Hit the sides, top etc and ask someone to watch for leaks on the inside. I would do this with the slide in and out. When the slide is in, spray the water parallel to the rig to simulate driving down the road as well as sitting still.
Last step, recheck those bags to see if the pressure has dropped.
Or you can pay for a mobile repair tech to come and do the inspection for you to the tune of about 500 - 1k. If you see any of these ask for them to be addressed before you sign the dotted line. If you don't want to deal with any fixes think of that money as payment for time not lost!