Smaller apartment buildings (less than 6 stories) might just use the regular waste management collection service. For the city of Pittsburgh, this will mean the city’s trash collection. Taller buildings will likely need to use a private company such as WM. Depending on how trash is calculated will depend on whether the tenant is responsible for trash or not. If the customer has to buy bags as payment for trash service, then the tenant will be responsible for their trash. If trash is charged to the owner of the building, then the realty company will pay for trash services.