| Business | Phone |
| Apex Development Corp 577 Main St, Islip 11751 | (631) 277-7638 |
| Arlene Realty Inc 191 Islip Ave, Islip 11751 | (631) 277-5000 |
| Cherveny Real Estate 19 Casino Walk, Islip 11751 | (631) 583-8718 |
| Coley-Haynes Realty Inc 372 Islip Ave, Islip 11751 | (631) 277-8804 |
| Devaney Realty 724 Main St, Islip 11751 | (631) 277-7919 |
| Era Hamlet Realty 554 Islip Ave, Islip 11751 | (631) 277-2300 |
| Hamlet Realty 554 Islip Ave, Islip 11751 | (631) 234-4029 |
| Terrace Homes Realty 229 Islip Ave, Islip 11751 | (631) 224-4300 |
| Universal Homes Realty 169 Islip Ave, Islip 11751 | (631) 206-4663 |