Mobile homes can often be a treasure trove. In the 50s and 60s before the placement of mobile homes was zoned more heavily they were often parked near other homes in the backyard or such as an accessory building perhaps for a relative. As that relative or tenant moves on or if the home becomes unlivable sometimes they were kept as a storage shed. People don't often spend a lot of $$ to update them and as a result they can be found in original condition.