It helps immensely on cost of chassis maintenance if storing your rig indoors. Tires and disk brakes go bad so fast when storing outdoors. But a lot of other things also age quickly.
We bought our 23.5 foot RV E350 chassis rig new in 2007 and have always stored it in our dry under-the-house garage. It is kept cool in summer and warm in winter with no concern of rodents or insects. We average a low 3300 miles per year. After the initial investment in getting the suspension right when new, the only investment in chassis maintenance has been one battery, some air and oil filters, and motor oil. I did replace the shocks myself last year with heavy duty Bilsteins. Our tires are 12.5 year originals of which I plan to replace them prior to our next big road trip out west. Brake and transmission fluid changes are coming soon which I will be doing myself.
Our 2007 E350 chassis has been VERY VERY cheap to maintain. I am so glad we have the E350 and not a Sprinter diesel. I could never afford to own one of them. For one thing, we don't drive enough to justify such expense. You have to drive them a lot for any kind of financial benefit.
Today, our rig still passes as brand new to people who don't know any better. Indoor storage is "The Way To Go" if you can arrange it.