Back End Database for my Company

Hi, I hired someone to complete a job for me and got ripped off but I did manage to get something - html files which I have attached. I am looking for a backend database for my real estate company. I want it be accessible by the web - and of course I want to assign username s and passwords to my agents so that they can access it when they are an agent with me, and cannot access it if they no longer work with me. When the agent logs in I want the database to determine what levelof authority they have. If they are rental agents they can only view listings and cannot edit anything. If they are listing agents they can add listings as well as view listings but they have no other administrative rights. Then I want the administrator level/broker and I want to be able to do everything: assign username/passwords, change people's status (type of agent), give rights and take away rights, edit landlord's information, etc. The files below are just the basic pages but I want it to be the agent logs in and is taken to a search page. Then, the agent puts in the criteria and based on that information a list is pulled up of all of the listings which apply. Then, the agent can click on which ever listing applies and see the details. I want the agent to be able to see everything except for the bottom information, which is the landlord's contact information. Listing agent: The agent goes to add listings - fills in the information and adds the listing. The listing agent can only see contact information for his/her listings and noone else's. The listing agent can only edit his/her listings and noone else's. Also, the original date a listing is posted cannot be altered to get higher up on the list of listings. I also wanted to be able to put pictures which are automatically resized but if that will be too much for my server to handle I can scrap that idea. Please respond with how long it will take for you to do this and your bid price. Bear in mind the design aspect is pretty much already completed. Oh, also so you can see what I am working with my host is [login to view URL] and if you click on compare packages I have the wordpress blog plan