opencart expert needed for upgrade of current open cart site to new version and template

We have an ecommerce website running on an old opencart software version I am looking to: 1. Upgrade this to latest version of open cart 2. migrate product to new site including offers etc 3. have a new modern, updated template/theme as our current website is about 2 years old now and needs a fresh design/theme. 4. improve checkout options to include some other options 5. make better compatible with google merchant systems and working product feeds. i think because our current open cart system is soo old, its best to create a new installation and manually add the existing inventory to it. this way its a new start with fresh latest program/extention versions. our current website "www . gad get grill .co m" (remove spaces)