| Business | Phone |
| Platt Processing Svc 16845 Blanco Rd 204, San Antonio 78232 | (210) 764-7733 |
| Stewart Geo Technologies Inc 5730 Northwest Pkwy 500, San Antonio 78249 | (210) 684-2147 |
| W F Castella & Assoc Inc 6800 Park Ten Blvd 180, San Antonio 78213 | (210) 734-5351 |