I'm considering buying a historic home >100 years old on the Chicago north shore and am trying to quantify/budget for the most expensive risks. I assume the foundation is one of the most expensive potential problems.

I'm wondering about when foundation problems tend to occur. Do they correlate strongly to the age of the home? Is there a certain age at which foundation problems become more likely?

If the foundation has repaired, does that mean that problems are more (or less) likely to return for a long time?