Average Hourly Cost: The average hourly cost of marble countertop installation by a marble contractor in 2023 is approximately $60 - $80 per hour.

Cost Breakdown: The cost of marble countertop installation is typically broken down into the cost of materials, labor, and installation. The cost of materials includes the marble slab, adhesive, sealant, and other necessary materials. Labor costs typically include the cost of the contractor's time and any subcontractor labor. Installation costs include the cost of the contractor's equipment and any subcontractor installation fees.

Factors Affecting Cost: Several factors can affect the cost of marble countertop installation. The type and quality of the accessory, such as the sink and faucet, will influence the cost. The complexity of the job, such as the size and shape of the countertop, will also affect the overall cost. The location and service provider can also affect the cost.