Lumber, drywall, plaster, lath, roofing, flooring, trim, cabinets, fixtures, and general cleanout junk are all fine to load. The restrictions come from New York State rules and from what the county transfer station refuses.
New York makes it illegal to put rechargeable batteries in the trash, including lithium ion, nickel-cadmium, nickel metal hydride, sealed lead, and the battery packs in cordless tools. Stores that sell them have to take them back under state law.
Electronics carry a statewide disposal ban too. Televisions, monitors, computers, and printers have to be recycled rather than thrown out, and free drop-off is available across the state.
Paint has its own route. Latex, acrylic, water-based, and oil-based paint are all accepted through the state's paint stewardship program and at the county's hazardous materials collection events.
Hazardous waste, liquids, solvents, fuel, and asbestos stay out of a standard container. Tires, propane tanks, and appliances with refrigerant also need to be set aside, and the county drop-off area in Newburgh takes those separately. Ask your account manager before any questionable item goes in.