| Business | Phone |
| General Concepts Corp 21660 Copley Dr # 320, Diamond Bar 91765 | (909) 860-7400 |
| Virdi International Corp 21660 Copley Dr, Diamond Bar 91765 | (909) 860-2328 |
| Jcc Homes 3209 S Brea Canyon Rd, Diamond Bar 91765 | (909) 594-7220 |
| O C Land Development 3620 Calmbrook Ln, Diamond Bar 91765 | (909) 396-8600 |