OsCommerce Modifications Needed - Urgent

Hello Freelancers! We need an OsCommerce expert to make some simple modifications to our shopping cart. 1) Need a system where customer can only buy ONE product quantity per customer. So if we sell a product, I need it so every customer can only buy one of that product, but they can buy multiple products. So they can buy product 1 and product 2, but not 2x of product 1 2) The customer MUST sign-up (become a member) before they can check-out and buy 3) The form which the customer uses to register, we need to add more fields/details to that form 4) A system where we can click on a specific product, and we can see a list of all customers who have purchased that product. 5) When customer buys a product, they should get an email saying 'Thank You...' and admin should get an email saying 'Customer Name has just purchased xxx' The idea behind this cart is: We are a youth-club which hosts activities, and we are going to sell tickets to the projects we host on this cart, so this is why we need these modifications. There are these Add-ons which will do most of the above modifications, so you may just need to install them: [login to view URL] [login to view URL],4155/page,4 I need this modifications completed within a day (within a few hours if possible)!!! I need a very cheap price for this, as the work is not too complex! Thank You