There are a lot of factors to consider when computing for the overall cost of a stone pavers Charlestown project. These factors include the cost of the materials, the location of where it will be installed, the labor cost and other related materials. For a typical 120 square feet project, homeowners spend around $350 to $550. That is around $3 to $5 per square foot for a 6 inches by 12 inches natural stone paver, unsealed and 3 cm thick. Professionally installing the pavers generally takes around 12 to 14 hours and can cost you around $730 to $1200. This labor cost amount includes the layout and preparations needed in installing the pavers like excavation, adding base gravel, edging the borders, and bedding sand. Most contractors also include the fabrication, setting and leveling of the stones, and applying polymer sand to joints. This also covers the requirements of planning, purchasing of materials and cleanup of the area after the project.