My house was technically built in 1897 but was moved in the 1920s on to a new foundation and we basically knocked the entire thing down and rebuilt it a few years ago after we bought it. Now we're adding to it again. It shares some of the DNA of that house from 1897 but basically none of the parts anymore and is much nicer looking whilst keeping the old timey style.
My contractor for a couple of big renovations I did figured that the 4x4-ish posts on the first floor were probably original along with at least some of the subflooring (about half of which I redid because it was collapsing). We think there was a substantial addition (probably including a second floor) around 1900. That's when the demolished barn on the now adjacent property dated to.
The house I grew up in was similar. It dated to either the 1700s or possibly even late 1600s. But the original house was just two rooms (two stories) built into the side of a hill.