shopify enquiry

hi I have set up a trial on shopify. I would like to enquire about pricing to see whether to go ahead with shopify or not. i would like to launch a cellphone store which sells accessories i would like to enquire on the cost and time to implement a number of things: 1. sort by name, price etc. (at top of each page) 2. 3 tier sub category menu (i.e. side menu must have "accesories" > "headphones"(all items) > (brands) 3. wholesaler app (happy to purchase but need someone to install it for me - installation instructions) 4. recently viewed items 5. need a theme with a responsive design for mobile and tablets thank you