and shop to my classifieds website

Shop section in my website : [login to view URL] this is osclass script , and i want have shop on my site where user can order online and can pay online , where admin can create offers etc . reference site link : [login to view URL] this design i like , so i want similar decent design ... if its not possible to create this option in my same site , we can go with [login to view URL] but i prefer to get access to subdomain with 1 login .. and we should be able to desplay subdomain / shop items on our main home page as well. thank u my first perference is to add the shop to current site ... without subdomain.