| Business | Phone |
| Grimes Investigative Svc Po Box 5695, San Francisco 94083 | (650) 873-8873 |
| Alex Kline Invstgtn & Research 1606 Stockton St, San Francisco 94133 | (415) 544-0300 |
| Barbary Coast Investigations Po Box 347308, San Francisco 94134 | (415) 467-5882 |
| Barry Simon Investigations 1606 Stockton St, San Francisco 94133 | (415) 788-7778 |
| John Blackburn San Francisco 94105 | (415) 979-0445 |
| Chayra Investigative Svc Inc 330 Townsend St, San Francisco 94107 | (415) 357-1134 |
| D F Leary & Assoc 110 Sutter St # 330, San Francisco 94104 | (415) 982-7157 |
| D L Price Investigations Inc Po Box 475875, San Francisco 94147 | (310) 273-2127 |
| Dale Investigations San Francisco 94110 | (415) 695-9616 |
| David Perticone Investigations San Francisco 94111 | (415) 392-3774 |
| De La Pena & Assoc 2711 Hyde St # 2, San Francisco 94109 | (415) 981-1841 |
| De Larios Investigations 209 Golden Gate Ave, San Francisco 94102 | (415) 252-7432 |
| Derish Associates Inc San Francisco 94110 | (415) 648-7007 |
| Dl Price Investigations 2269 Chestnut St Pmb 281, San Francisco 94123 | (415) 749-1919 |
| Elder Angels 350 Townsend St, San Francisco 94107 | (415) 284-1160 |
| Fechheimer Investigations 2005 Lyon St, San Francisco 94115 | (415) 885-5918 |
| Glass Key Investigations Po Box 12367, San Francisco 94112 | (415) 334-0856 |
| Heritage Research Group 110 Pacific Ave, San Francisco 94111 | (415) 437-0152 |
| Howard Street Investigations 923 Folsom St # 306, San Francisco 94107 | (530) 828-2859 |
| Immendorf & Co Investigations Po Box 470190, San Francisco 94147 | (415) 776-7777 |
| Jayson Wechter & Assoc San Francisco 94122 | (415) 664-3900 |
| Kroll Associates 90 New Montgomery St # 315, San Francisco 94105 | (415) 495-2200 |
| Krotzer Legal Investigations San Francisco 94105 | (415) 495-7272 |
| Lipset Service 2509 Pacific Ave, San Francisco 94115 | (415) 421-9137 |
| Multifaceted Productions 5214 Diamond Heights Blvd # F, San Francisco 94131 | (415) 566-5135 |
| Murphy & Assoc Inc 1440 Florida St, San Francisco 94110 | (415) 647-9860 |
| Myres Investigations Po Box 883992, San Francisco 94188 | (415) 468-9193 |
| Neilson & Macritchie Invstgtrs 293 8th St # 1, San Francisco 94103 | (415) 585-0303 |
| O'Brien & Assoc 806 22nd St, San Francisco 94107 | (415) 647-9999 |
| Passanisi Investigations 4228 18th St, San Francisco 94114 | (415) 703-9888 |
| Pemberton & Assoc 600 Townsend St, San Francisco 94103 | (415) 522-0840 |
| People's Eye 211 Gough St # 111, San Francisco 94102 | (415) 861-0351 |
| Perez Investigations Inc San Francisco 94110 | (415) 206-1761 |
| Peter Gessner Investigations Po Box 410691, San Francisco 94141 | (415) 821-4300 |
| Private Inquiries San Francisco 94110 | (415) 826-3598 |
| Probus Research 601 Van Ness Ave, San Francisco 94102 | (415) 440-9100 |
| Ribak Research & Investigation San Francisco 94111 | (415) 296-9251 |
| Robert J Holmes Investigations 507 Polk St, San Francisco 94102 | (415) 771-2073 |
| Safir Rosetti 717 California St, San Francisco 94108 | (415) 433-9270 |
| Sam Brown Group Inc 1255 Post St # 740, San Francisco 94109 | (415) 621-5918 |
| Sjg & Assoc 1388 Sutter St, San Francisco 94109 | (510) 923-7666 |
| Skye Investigation 350 Townsend St, San Francisco 94107 | (415) 284-1165 |
| Stuart Kohler & Assoc San Francisco 94103 | (415) 626-7400 |
| Submar Investigations San Francisco 94111 | (415) 675-9738 |
| Sullivan Assoc Intl 4644 Geary Blvd # 130, San Francisco 94118 | (415) 221-6136 |
| Timeline Investigative Svc 300 Montgomery St, San Francisco 94104 | (415) 352-1062 |