Web development -- 2

I need a new website. I need you to design and build a website for my small business. I'm a startup ecommerce company. My platform serves as digital currency exchanger or e-currency exchange, aimed at providing individuals and businesses a world class experience to buy and sell cutting-edge e currencies. ie. A customer wants to fund his e currency account ( Bitcoin ) to be able to complete this transaction he needs to first find an E-currency Exchanger ( ME ) place an order for the e-currency he wants to buy and make payments to the E-currency Exchanger ( ME ) either through a payment gateway provider, Bank wire or Money transfer services or at Point of sale. The Ecurrency Exchanger ( ME ) receiving payment will now fund the customer's e-currency account.( Customer's Bitcoin address ). So on my E-currency exchange website a customer can get information on the exchange rates, ecurrencies in stock, order information and payment information. I want a website implemented on a responsive front end, so the website will adapt for Mobile, Tablet and Desktop PC access. It should be built on a Content Management System which would enable me to manage sites content and set my exchange rates. The front end would offer users a calculator which can then be used to facilitate the purchase of bitcoins and other e-currencies in either USD or GHS [login to view URL] website would be integrated to a Payment Gateway ( [login to view URL] ).