Custom web shop

I am looking for a coder to build a custom web shop in PHP and MySQL. ? The webshop will take customer's window sizes and provide them custom curtains, as such off the shelf store packages are not suitable. ? The system will need to integrate with the Saasu finance package using their API. ? The system will need to handle registration of users, a shopping cart that caters for multiple windows. ? The store will also need to connect to a credit card payment gateway and allow for paypal payment. I will be responsible for user interface design and the graphic design and will specify requirements in detail. ? I have previous coding experience so I understand what a coder will be looking for in terms of requirements. Providing approximate total costings for will help guide my selection. ? Also, if there are tools available to eliminate some of the required work then I am interested.