Need a cms system adding to my website

I need a cms system adding to my website once it has been designed,about 2-6wks.I also need an integrated e commerce payments system adding.

We need the cms system to enable us to edit our website to add new products etc without having to code this.We need E commerce payments such as paypal and the major credit cards adding for payment of our products.We also need a shopping cart adding which will also stock control for us and also retain information of customers who have used our site and provide us with any relevant information.