This estimate is to replace a dual check valve. The scope of work includes the removal and replacement of the existing valve, as well as any necessary modifications to the piping system. The new valve will be a type that is compatible with the existing system and will be installed in accordance with the manufacturer's specifications. The cost of the estimate includes the labor, materials, and any permits or inspections that may be required. The estimate also includes a contingency allowance for any unexpected costs that may arise during the installation process. If you have any questions or concerns about this estimate, please do not hesitate to contact me. I look forward to working with you on this project.