Wordpress site redesign and product addition

General information for the website: Online Retail
Kind of development: Customization of existing website
Description of requirements/features: We have a website http://www.enpee.co.uk that is running on wordpress. Our website advertises and sells our juicers and blenders but our company has changed into offering many more items such as computer monitor stands and mounts and we want a redesign of our wordpress site to reflect this

At the moment we are using the Kallyas theme and that works well for us as its simple to use but if you suggest something better then we are willing to consider.

1. Our site is easy to navigate and we want to keep this easy navigation structure for the customer. We accept paypal and credit cards through sagepay, and want to add a module that accepts Amazon Payments too.

2. We want all the existing products to be on the new site and also approx 40 more items to be added - these products already exist on ebay/amazon etc so you can scrape the description if necessary from there

We are looking for a wordpress EXPERT. Someone that can diagnose and fix problems - not just a simple install and go module, for example we have not been able to add Amazon payments from our last 2 hourlies as they have not done it before .

Let us know your thoughts, price and mock ups if necessary. Thank you
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