Hello,
I'm new user of this site, but I'm not new to web development,web design.
I understand your need of redesign/refresh/update your site with Wordpress.
I could do that for you, as I have +3 years of experience in Wordpress. I did already pages like wordpress + ecomerce site. If you need I could show them to you because most of them are offline :)
I have great knowledge of HTML,CSS,PHP,Wordpress and strong knowledge of Javascript. I have HTML certification and currently working on more certifications. As i mentioned before, I have more that 3 years of wordpress development/implementation/design.
I think the best strategy to make you spend less money, is to buy template(as you mentioned to freshen appearance), and use it. Then I should use plug in called ecommerce plugin from woothemes(free), that gives you functionalities of e-commerce site(shoping card, login,register,comment,etc...). I would activate plugin Jetbox(site statistics) and connect wordpress site to google analytics(more detailed site statistics).
If you like my proposal you should contact me , and we can agree for metting on skype,or anything else you have in mind.
Yours sincerly
Aleš Petrovački
Alki-RS