Does The Dumpster Size Affect The Rental Cost? It is critical for a customer to understand the cost of a dumpster rental before using one for their trash management requirements. Dumpsters are typically priced based on the amount of garbage they can hold. The size of the dumpster required is determined by the amount of waste left over. If the project is little, a basic 20-yard dumpster will serve. If the job is huge and produces a lot of...