Complex sentence: Erected in 1871, the home is one of the oldest surviving structures in Davenport's upper Main Street area--if not the oldest--and was originally reported to be "the most commanding structure" in the neighborhood.
Split into simpler sentences: Erected in 1871, the home is one of the oldest surviving structures in Davenport's upper Main Street area--if not the oldest. It was originally reported to be "the most commanding structure" in the neighborhood.