Need a PHP programmer to set up a merchant account API

We need a programmer to install a merchant account API into our web site, so our web site can start billing customers automatically whenever they place an order. We will provide all of the documentation from the merchant account provider. Please only bid if you have experience doing this type of work, and are willing to complete this project within the requested time frame. GAF escrow only. We need this done extremely quickly (max 1 days)