Only a handful of other cities have even tried housing 1,000 people in one spot, and most, if not all, had far more space to work with than the warehouse’s nearly 65,000 square feet.

Foxconn’s buildings in Wisconsin were always empty, even though the company insisted they weren’t. Now they’re for sale.

Other recent deals in Riverside include Union Bank’s $4.3 million-per-acre deal for an empty plot of land, and BentallGreenOak’s $120 million trade for a 361,346-square-foot development. The average ...