All depends on the cause and if it's "done" or still moving.

Our "middle" section is leaning about 1" to the north from the floor to the ceiling. The floor also had about a 1" drop in it from one end to the other.

As to the lean, this part is built with square nails, and was moved to the property and attached the the existing structure some time around 1900. Don't know exactly how old it is, but it's older than the structure it was moved next to. From what I can tell, it was leaning when they brought it here, and the other parts are firmly attached to it the way it is. It is not going to go any farther, but it would mean tearing the house apart to straighten it back out.

With the floor, that was just the foundation settling. Did not look like anything had moved near 100 years though. Sill and boards were solid, so we just built up the one end when we rebuilt the floor.

Another part of the house, the sill and ends of the joists had rotten off. Looks like the water damage had happened about 50 years ago, and it has slowly been decaying. It had about a 3" slope to the floor, but the building was still relativly plumb. We expected settling, but we very surprised at just how much rot we found once we got down to the joists - good thing we never put our waterbed in that end of the room!

Both these areas had so many layers of wallpaper, I don't know if a crack would have shown through anyway. On the second, we had to jack up the whole side of the house to rebuild the sill.

If you can get under the house to check out the foundation, and if not pull off the siding and have a look see. In the first part, we could have ignored the problem for another 100 years - in the second, I'm amazed the house had not slipped off the foundation. I think if it weren't for the ballon framing holding the walls in place, they would have moved.

Cathy

I guess the first thing you should do to re-read the inspection report that I assume you obtianed before you bought the house. If the condition is obvious to you, it should have been obvious to the inspector and he should have commented on it in the report.

If, for some reason, you do not get any clarity from the pre-purchase inspection report, it might be a good idea to have a structural engineer look at it, or someone else with a trained eye, probably a licensed house inspector. The cost should not be very high for assessing just this one issue. They see things very differently to "regular" people, and can give you an informed opinion of the condition and recommend what, if anything, should be done to correct it or to prevent worsening. Just make sure the person who inspects your house is impartial, which means that he is not a contractor who will then propose to do the remediation.

And if you do get an outside opinion, I'd find someone who specializes in old homes. New home inspectors won't have a clue about old homes. Get good referrals.