Dealer/Supplier Mysql/php/html Interface

Hi, This is Phase 1 to a Dealer/Supplier Interface I need for a client. This will be the Supplier point of view to the Dealer/Supplier Interface. Me as the supplier must be able to: 1) An initial screen with a drop down box of all My dealers....This list will come from a existing Mysql database of dealers. 2) Once the Supplier selects a Dealer he must then fill in the Name of Job Site. 3) Then the supplier will be given the option to input the name of each Lot for the job site. In other words there is one dealer who can have many job sites and each job sites can have 1 to many lots. Once all that is set. The Supplier will be presented with a screen that will have a list (check boxs and details) of His inventory of product A (a table will hold that list) and allow supplier to choose what products from that list will be available to that dealer/for that job site. That will be stored for furture use. A 2nd and 3rd screen will follow as 1st is completed with Product B and Product C. The supplier will need to be able to add,delete,change from Product List A,B,C. Also be able to change after set the selections he has set up for dealer/jobsite. 1) Add More lot's or change selection of product lists.