boston Dirt

Hey, I’m looking to build a site that I believe is pretty simple but I am not sure how to do it. The premise for the site is a clearing house for dirt in the Boston area. On the home page I want it to say “Boston Dirt??. Under there would be two links. One will say “Looking to Buy??, the other will say “Looking to Sell??. Upon clicking on these links it should take you to a page where you can search through a database where people have put up the different things that they have. After someone searches for something and clicks on it I want them to be able to see the description of the item, but have to pay one dollar, or any amount that I want, to see the contact information. People should be able to make an account with the site and each person should be able to add to the database and pay to see contact information. I would like it to be in HTML as much as possible so I can change it around a later. Let me know what you think, how much it would cost.