maintenance increase & assessment

We live in a small building in a coop/loft and have recently been hit with a 50+% maintenance increase. We were stunned by the large increase and are now extremely worried that this will effect the marketability of our apartment and investment. The increase, we have been told, is meant to replenish the reserve fund. On top of this increase we also will be hit with an assessment of ca. $ 25,000 for the upcoming renewal of the elevator. Does that sound right? Does anyone have an alternate suggestion for financing these two substantial expenses? Also, any suggestion on the 'rule of thumb' of maintenance per square foot? Our apartment/loft is between 2,5oo and 3,ooo square fee