The disparity between how nice the outside looks and that floor inside is pretty large. The inside has clearly gotten regularly soaked; you can see rust on almost everything at floor level (especially on the wheelchair lift).
I would pass on this bus, as much because it's a 2012 as anything else. A bus this new can still legally carry children in any state, so you'll have more bidding competition.
Also, this may not be relevant to you, but raising the roof on a C2 is difficult because of the inward-slope of the walls starting below the windows. This also limits your interior space a bit, especially with airplane-style storage compartments.