Ordinary construction and household debris is welcome. The limits come from a short state list and from what the receiving site will accept.
Colorado's own rules are brief. The Colorado Department of Public Health and Environment bars five things from any solid waste site in the state: lead-acid batteries, used oil, waste tires, waste electronic devices and computers, and liquid waste or anything holding free liquids unless that particular facility is approved to take it.
That electronics rule catches a lot of cleanouts. Monitors, laptops, printers, and televisions all have to come out of the load before the container ships.
On top of the state list, hazardous waste, paint, solvents, fuel, and asbestos never belong in a standard container. Appliances holding refrigerant need a technician to recover it first.
If a cleanout turns up paint cans, chemicals, or old electronics, your account manager can point you to the county facility that takes them so one banned item does not hold up the whole load.