Create electrical estimating tool using PHP & MySQL

I am looking for someone who can help me develop an online tool that functions as an electrical/solar estimation tool. I need to be able to create/add/edit databases from tables in the National Electrical Code (e.g. temperature derates based on temperature ranges in both C & F, tables which have wire sizes and ratings based on a certain wire type, etc.). I will also need to be able to input solar module and inverter specifications that will be used in the calculation of voltage drop, wire size, etc. (I can provide the formulas). I will need an online interface in which I can edit product details and add/remove/disable new products. We will need to create a database to store "projects" as clients work on specific ones. I'll need to be able to have real-time updates (versus having to 'save' and/or hit 'refresh'). Probably the creation/population of 10-15 tables. I will then need to create tables where we can input distances and select product information. I have an excel spreadsheet which currently does most of the work right now, but i'm looking to create a web accessible tool that I can let other users (password protected) use.