Jenn:
I realize this comment doesn't address your concerns over stone foundations,but...
...if I were you, I would look for a house built between 1950 and 1970.
The reason why is that copper plumbing became common around 1950. Prior to that most houses were plumbed with iron supply pipes, and they gradually cake up with rust on the inside, discolouring the water and pinching off the maximum flow rate.
Also, after 1970 was when the baby boomers were all getting married and buying homes to start families in. That created a great demand for houses, and so plumbers, electricians and carpenters all started demanding higher wages, and the price of houses shot up. As a result, builders tried to keep the cost of houses affordable by lobbying the government to lower the standards of residential building codes. And, the government complied. That's when you saw aluminum electrical wiring showing up in houses cuz it was cheaper than copper wiring. And, fir wall studs got replaced with spruce wall studs. (You can't even find fir wall studs for sale anymore!) And particle board underlayment replaced fir plywood underlayment and fir plywood or lumber gave way to spruce plywood subfloors and so on.
I don't know if this is the case in the US, but I was told according to our Canadian government, spruce is just as strong as fir. That reminds me of the joke: "If ducks are considered to be geese, then if you have 18 ducks and 16 geese, how many geese do you have in total?"
Sixteen. Calling a duck a goose doesn't make it a goose.
And, if it wuz me, I would try to find a house that hasn't had it's basement renovated or a deck added in the back yard and that wasn't renovated by the current home owner. The reason is that the homeowner is going to want you to assess the value of his work as that of a professional. Whereas, this might have been the first time he's done these kinds of projects, and the renovations he's wanting you to buy for top dollar contain all of his learning mistakes. At least with no renovations, you won't be paying extra for bad decisions, dumb mistakes and/or built-in problems made on his way up the learning curve.
(I don't think that stone foundations are as much of a problem as buying a house that was built at a time when fuel was cheap and insulation unheard of. It's all the other technologies of the time that would need to be updated as well, like the plumbing, electrical wiring, windows, heating system, etc. and all of the technologies in the house that are no longer current; like ornamental plaster crown moldings and such. If there's a roof leak and that plaster gets damaged, who does that kind of work anymore, and how much is it gonna cost to fix?)
