Customisation of php shopping cart script

I need a php open source shopping cart script to be modified to have the following features. I have been looking at OSCommerce, but am also open to using other scripts if it will produce a better result. 1. A vertical layout for the products (eg 10 per page). Each product needs to have a 1-3 line description, a quantity box and the add to cart/buy now button on the same line so customers can select and buy many items without needing to click into other pages. 2. A unit to be customisable for each product eg. a weight(kg) or a packet or a box. 3. In the quantity box, can put in portions/decimals eg 0.2 or 0.5 kg, and have price automatically adjust. 4. In the admin panel, a user can easily add new products and be able to select units eg. kg or pack. Also that the user can select products to be hidden when unavailable. Note: This is code/template customisation only, not setup/design work. In the final form, I want the script to be ready to install, and only require colour changes, logo additions in order to be set up and used. This work is for a client and depends on the price and whether it is signed off to be done or not. Thankyou for your patience. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). * * *This broadcast message was sent to all bidders on Thursday Dec 20, 2007 4:40:47 PM: Hi, Thankyou very much for your interest and bids on this project. I have made a few changes to the bid request and extended the bidding deadline. This project is for a client of mine who is still deciding whether to go ahead and what he wants, so sorry for the delay. Thanks for your patience. ## Platform php / MySQL on Unix server