Landmark Realty of LI, Inc. Share: Real Estate/Real Estate Services Landmark Realty of LI, Inc. Visit Website Request Info 6347 Rt. 25A Wading River, NY 11792 631-929-3600 X 309 About Map About Real Estate Broker in Wading River. We service all real estate needs whether someone is looking to buy, sell or lease residential, commercial, land, new construction and relocation services. What's Nearby? Distance: 5 10 15 20 25 50 mi.