1969, eh? OK, sight unseen, and no specifications, let's see:
Lead paint, aluminum wire, asbestos shielding, low test concrete side walks and drives, and galvanized pipe....
About $25.00 a square foot before updates, and $80.00 - $100.00 a sq. ft after meeting code. Depending on location, of course.
My point: How do you put a price on any item you know so little about?