| Business | Phone |
| Conceptual Design Engnrng Inc 98 Vinings Dr, Mcdonough 30253 | (678) 610-5406 |
| Cornerstone Engineering Llc 125 Westridge Industrial Blvd, Mcdonough 30253 | (678) 432-1287 |
| D W Smith Design 23 Hampton St A, Mcdonough 30253 | (678) 583-5960 |
| Dorado Ventures 252 Keys Ferry St, Mcdonough 30253 | (678) 432-5720 |
| Pro Spec Engineering 455 Bridges Rd, Mcdonough 30253 | (678) 610-5004 |