| Business | Phone |
| Newton Investigation & Sec Waterloo 50701 | (319) 232-9097 |
| Reed Investigations 1932 W 3rd St, Waterloo 50701 | (319) 232-6934 |
| Cobra Investigations 807 Moir St, Waterloo 50701 | (319) 233-6519 |
| Flynn Investigations 532 Cataract Ave, Waterloo 50702 | (319) 232-2238 |
| Watchful Eyes Investigation 128 Niagara Dr, Waterloo 50701 | (319) 233-6596 |