While I'm new to Freelancer, I have been developing at a high level for over 20 years. I would greatly appreciate if you would take a look at my portfolio, here on Freelancer, to see the many large scale applications I've build over the years.
I'm also an American living here in Nevada. During your project I would make myself available to speak often on the phone, or via Skype, so you can quickly and easily communicate everything you need to make sure that this application is exactly what you want. This alone will add a great deal to the success of your project. Add that to my vast experience, and professionalism, and you're guaranteed a store that you're in love with.
I would very much love to talk more about your project.
Thanks so much for considering. Have a great one.