System Administrator for Ecommerce Startup

Hello, We are a retail fashion start up. We've developed our site using Prestashop as the shopping cart, but are currently managing our server and the site code ourselves. We are looking to outsource this job the keep the server updated, secure, and running well. There are also a few small coding sections, CSS changes, and possibly SEO work that are a bit beyond our scope. Looking for someone to take on this role as our go-to person. We prefer someone readily accessible, fluency in English is an absolute must. Work will be persistent as the site will constantly be changing and updated, we'd like someone we can develop a working relationship with. We are hoping to open our door this Monday so there will be immediate work if we can find the right person.