PHP Inventory/PO Database

I have a simple Microsoft Access database (which I created in less than 6 hours) that I want rewritten in PHP. Right now, it does about 3/4 of what I want it to do. There are three additional tables in the database that constitute a new Purchase Order module that I need in addition to the re-write. Phase One: Rewrite the existing database in PHP/MySQL (adding a Login screen for security) to Create the beginnings of an inventory database. Phase Two: Add Purchase Order module to the database given the three tables in the Access database that deal with that (tblPurchOrd, tblPOItems, & tblFeedback) I need a bid on what it would take to complete both phases. But I need to take delivery on each phase as we progress. Will pay after each phase as well. NOTE: This database must be absolutely secure. Therefore, it needs to either be written using an SSL certificate or EXTREMELY EASY to update code to work with the SSL certificate (changing local to absolute references & using "https://") and any other methods you use that would make it more secure.