Customizing a open cart / Design and features / logo

Hello, We would like to upgrade my E-commerce on Open Cart. Customs design needs works / Feature need works too. Logo need to be worked too... All is already installed but it's not very beautifull. I need more a designer than a programmer but the site should be set with the last SEO update. It should be like professsional and fully working. You should also set all the products features like / inventoy / taxes / and about / contact us / Privacy Policy etc,,,