This is not an uncommon issue when your plane lives in a hangar in which, shall we say, not everybody is pulling in the same direction.
I was in one of those for ~3 years, and would occassionally find some big twin parked in front of mine, and being the weekend the owner could not be contacted. This was despite having put a "aircraft will be required on Sunday" etc notice on the propeller.
There is no perfect solution to this kind of thing. If you want cheap hangarage then a "hangar co-op" type of arrangement will be the cheapest way but you need to make sure it runs smoothly.