| Business | Phone |
| Alexander & Bishop Ltd 222 Pearl Ave, Oshkosh 54901 | (920) 426-1404 |
| Centrum Development 375 City Ctr, Oshkosh 54901 | (920) 230-1463 |
| Century Capital Group 377 City Ctr, Oshkosh 54901 | (920) 426-1404 |
| Washington Development Corp 300 E Custer Ave, Oshkosh 54901 | (920) 231-1117 |
| Keystone Development 420 S Koeller St 230, Oshkosh 54902 | (920) 303-9404 |
| Midwest Real Estate Devel 100 N Westhaven Dr, Oshkosh 54904 | (920) 426-2001 |