Hi Wonder05,
Welcome to the Heartland Owners Forum.
Finding a never used 2012 trailer sounds pretty extraordinary.
A 2012 trailer may have been built as early as first-half of 2011, so the trailer may be 7 years old. There are some age-related things that you should consider. If this is on a dealer lot, it may never have gotten any maintenance at all.
No matter how it's been stored, all the caulking and sealants around lights, markers, A/C unit, fans, skylights, etc. all needs to be re-done. The tires have aged out, regardless of how they look. If they're claimed to be replacement tires, check the date code stamped on the tire sidewall. The wheel bearings need to be repacked (not just have grease added). You need to inspect very closely for any signs of water intrusion/delamination around the exterior, and any signs of water intrusion inside.