Hi,
I'm above you budget, but I thought I'd go ahead and respond.
I do almost exclusively Thesis work, and have done almost 40 websites in Wordpress/Thesis. Most recently, I just about have completed a site for a customer based on Wordpress and the WP-commerce plugin. So, I have a good sense of how this should be configured for maximum simplicity, flexibility, and overall usability.
I've been in your shoes. The thing I would suggest you think about, is that time is money. What's it worth to have someone that can understand what you're asking, ask the right questions to get moving, and keep you updated in the process?
If you're interested in trying out someone from the USA, I'm happy to do my best work for you.
Thanks!
William