Build an Online Store using custom template on big commerce

Hi, we have a childrens clothing business that is being run solely through facebook at the moment sales occur simply through people messaging and placing an order based on a hoto of an item they see. We require an online store to be built to run inline with a brand idea we have. We alsready have a logo that has been made which has a white background and a light purple colouring. We are in the process of purcashing a high endSLR camera to take better quality photos of the stock to them be uploaded using Big Commerce back end system. We require the site to be constructed using Big Commerce as this is the online shop tool we prefer having looked at all others that charge a monthly fee and includes hosting. We already have domain registered. We require someone with experience in onle stores with a creative ability to delever what we want in terms of the ongoing branding. We like the following sites which ours would follows similar in flow and design [login to view URL] (but with more of a laid back feel more modern) [login to view URL] [login to view URL] the site will need to be ipad and iphone mobile ready. so the site will be minimalist on its design. also requires a blog function.