Foundation Problems 101 -- Buying a Place With a Foundation Problem

[Brook W.]

I want to hear your most basic thoughts about buying properties with visible foundation problems. I understand there can be a huge spectrum of problems with consequences varying from "can't play a fair game of marbles" to "oh $hit the house is falling down the hill." I also know reasons for foundation issues can vary throughout the country; I live in a hilly city with clay-heavy soil and that affects how things work here.

Generally, do you consider purchasing a home with foundation problems? If you are doing buy-and-hold and you buy with the assumption that you can watch the foundation and perhaps install a French drain or push piers later, how do you strategize for future repairs? How do you figure out what will address the problem?

I want to hear all your thoughts about buying properties with foundation problems!