The budget for this project can be estimated based on the scope of work and the requirements for the contractor. Given that the project involves the installation of two new reduced pressure principle backflow prevention assemblies, the cost of materials and labor will be significant. Assuming an average cost of $10,000 to $20,000 per assembly, the total cost of materials would be around $20,000 to $40,000. Adding labor costs, which can range from $5,000 to $10,000 per assembly, the total labor cost would be around $10,000 to $20,000. Other costs, such as equipment, tools, permits, and insurance, may add another $5,000 to $10,000 to the total cost. Therefore, a reasonable estimate for the budget would be between $35,000 and $70,000. This estimate is based on the assumption that the contractor will need to provide all necessary materials, labor, and services to complete the work, and that the project will be completed within the specified 90-day timeframe.