Depends on far you want to go, cars I have known to be stored had lots of things deteriorate brake pads, anything made of rubber, clutch, earthing points (a biggy), interior (use those gel crystals that absorb water) to name a few. For the engine take off the tappet covers and spray every thing with at least lanox or heavier, without sparkies fill the motor to the top with a light oil and replace the plugs. Your valves and thier seats are the hardest to protect without getting oily shite in the zoorst but if you remove the manifolds its a breeze and tape up the holes. Condensation is your biggest threat, when the humidity rises in summer, it stays around and sits in places that it normal wouldn't, relays headlights etc.
If your past the Great divide its heaps better and the motor is your main concern.