I'm on my second Beaver and so far actual repair costs that were not self inflicted have been minimal. Still, there is the routine maintenance that must be performed but that would be true no matter what MH we have.
On the other hand my propensity for upgrading has certainly consumed a few $$$ but, in my mind, that's an elective and part of the fun of ownership.
Since we have bought both Beavers from a dealer that performs extensive PDI inspections there may have been a lot of issues that were resolved before we took delivery and we simply never knew about them. As a result there haven't been any significant surprises.
