| Business | Phone |
| Aapi 2805 E Washington Ave, Madison 53704 | (608) 345-0009 |
| Martin Security Investigations 2517 Seiferth Rd, Madison 53716 | (608) 222-0700 |
| Beneficial Investigations 3809 Cosgrove Dr, Madison 53719 | (608) 845-6420 |
| Discovery Investigations Po Box 8491, Madison 53708 | (608) 335-6309 |
| Fyi Investigations 10 E Doty St, Madison 53703 | (608) 444-3554 |