Website from WordPress Template with E-commerce Functionality

We are looking to get a website made using a WordPress template that we have, and modify it. Importantly, we will like to add an e-commerce/add to cart functionality to the website. Please see this website and if you can replicate this: http://technodroidcomputerstore.com. The funtionality where you click on one of the items and and then hit "add to cart". Also we would like to add a gallery functionality, like here: [login to view URL] And for this we may have to design a small CMS for this tab. IMPORTANT: Please give samples and examples of websites you have made but most importantly show us websites you have made with e-commerce and the 'add to cat' functionality. Also please give a time-line as to when this whole website would be completed. Thank you.