It was probably exposed to road salt in Indiana. I was told that these units that were built in the winter and pulled over the salt treated roads are supposed to be neutralized when they get to their destination.
I have a 2015 that has the same problem. I have neutralized all of the rust on the frames and the bolts and repainted them. I have not done anything to the springs yet.
I don't think the rust is anything serious but it does look bad and it will spread if it is not addressed.
If you don't mind a little manual labor maybe you can get a deep enough discount to make it worth your while.
There are rust neutralizers that you mix with water and spray on the rust and it does a good job of stopping the rust but you also need to paint it.
Good luck on your decision.
