Bank repo could be an issue, especially if they stripped it for any items of value.
Might be worth a flight out there.
We sold our 2007 Montana 3400 to a great couple in Georgia and they flew into Denver to take a look. Ours had been garaged so I was confident it would sell, and they turned out to be great folks we would like to visit again.
The Big Sky in 2008, if I remember correctly, got you exterior paint, larger tanks, leather furniture, better tires, bigger microwave, bigger fridge I believe. It was hard to track because everytime they added something to the Big Sky it would be added to the Montana the next year, and it got to the point the Big Sky is just a feature option with paint, levelers, and a few extra things for ~$10K add on. If RichFAA is on, he knows more about the Big Sky than I do as he recently bought one. Also the Montana Owners Club can give you an idea of what the differences were.