I need a website with two columns. Food menu will be on homepage. In the main column, menu headings will be listed on top and when someone clicks on a heading, it will scroll (or drop down) to that menu's area down there. Every menu item will only have one line or two with ingredients, no need to open a new page for details, but some of them will have size choice and the price will change with the size. For pizzas there should be an ingredients list if customer wants to add stuff, and it will change the price.
People will click add to cart icon or enter the number of item they want. At the same time, the cart should be updated with ajax, jquery, etc on the other column.
I want only members to order food, because the "only option to pay is at the delivery" and don't want to deal with false orders. They should have their contact information for delivery and mail adress for membership approving and updating their information.
On the backend, i would like to be able add/change items, prices etc. or if its a well commented script that may be enough.
On the checkout page, customers will write additional requests, choose the way they will pay (cash or credit card at delivery), approve the order and then the restaurant will get the order with their pos / receipt printer / fax machine.
If you already have a script for this purpose or you can modify a script or e-commerce cms, its ok for me too because i don't have much money and time.