I'm crying tears of blood for all you country folk who can't decide whereabouts on the gazillion acres under pitch dark skies to put the obs! I wish I had that much space to worry about such....
Seriously - I agree - option 3 as above..... although if you build the observatory so it can be reasonably easily dismantled and moved, you could do option 2 then switch to 3..... I made mine "movable" but now I think I'm dreaming.... turned out heavier/bigger than my mental blueprints had predicted!
How about option 1 with the phone-a-friend-with-the-chainsaw lifeline???