Found in the Watertown (WI) Republican on the Chronicling America website (free):
Jun 11, 1879
Thos. McComb has sold his block near the bridge to Mr. J. Haubert, of Whitewater, for $1600. Mr. J. Haubert occupies a portion of the same with one of the Harness Shops in the county, and, we understand, contemplates erecting a respectable brick block on the ground sometime in the near future.
Oct 5, 1881
Some one broke a pane of glass out of Haubert's harness shop Tuesday night and helped themselves to what whips they wanted.
Dec 5, 1883
H C McMillen, of Johnson's Creek has bought the Haubert Block near the bridge. He contemplates the erection of a substantial brick block on the same lot. Should he do so it will prove a profitable investment.
Unfortunately, I found no advertisements for the Haubert harness shop. And, it's not clear whether the harness shop was in Watertown or Ft. Atkinson. But, maybe these snippets will help nail down the period when Mr Haubert was in Jefferson County.