If one wants to build in Italy, it’s usually best to figure out a way to do that without having a foundation...at least if you want to keep schedule.
Five or so years ago I was at home a lot (for some reason, heh) and watched a lot of vids about those one-euro fixer uppers in Italy. One of the vids that the guy wandered through an entirely empty ruined mountain village (there are some few of these, a big quake after WWII wrecked them, and the gubmint built no doubt very attractive apartment buildings down the slope a bit from each site).
I noticed one doorway was framed in tiles, and they appeared to be those kind that were used in the walls of the calderiums to keep the chamber pipin’ hot. Naturally I could be mistaken, but if so, it suggests that there are or at least were ruins of a pretty posh Roman villa that wound up being used as a source of building materials.
Gotta say, I’m a little jealous.