True, but houses like that are far more expensive to build today. I'm not sure you could "flip" a new home built with traditional masonry since it would require a larger upfront investment. (Edit to add: the normal American usage of "flip" (buying a degraded property, fixing it up, and reselling) is also not really applicable to houses in move-in-ready condition.)

The original construction costs will probably have been recouped after 370 years of continuous occupancy, though. :)