I agree with Jeff. Concentrate on the structure itself, then do finish and
cosmetic repairs. Does the foundation need repair? Do any support beams
need replacing? Upgrade your plumbing, electrical, and HVAC systems before
finishing walls. Anything that is causing continual degradation, such as a
roof leaking, should be addressed first.

Err... after actual hazards. Loose ( steps, rails, wiring, bricks in chimney)
*Then* problems that threaten the structure (bug and water control)
Then things that are costing you money.. (insulation, draft control)

--Goedjn