House is lacking foundation

[Tyler D.]

I'm looking at buying a fixer property, and found one that is in a good part of town, great price, with mostly cosmetic fixes required.

However, the house does not have a crawlspace and is at least partially missing its foundation. The upside is that the house is over 100 years old and still standing, and the seller is very motivated as this issue makes it hard to sell. 

As I'm a buy and hold investor, would it be smart or foolish to buy this house without a foundation? I would be willing to fix this problem if it's affordable, and would also be willing to let it ride if it is not an issue, as the house has been just fine without it for a long time.

What do you recommend?