Online Store for computer store & inventory system in Magento

We need website for sale & purchase of item for our current market base in EU & UK 1. We require our home page to assign language and currency base on the IP of customer and also offer option of choosing by customer by clicking the flag of following UK, Ireland, Germany , France,Spain ,Italy, Belgium , Switzerland,Poland , Netherlands,. for sale side some thing like [login to view URL] [login to view URL] we sell mainly apple but also windows computers , Laptops , tablets n Samsung phones too. I have the homepage design ready and i can provide the PSD 2. We wish to have buy back option for our customer like following pages [login to view URL] [login to view URL] [login to view URL] we will buy all Apple products only 3. We want a page where customer can request for RMA ( Return Marchendise Authorisation) and once approved they can book return label ( we will provide the code from our carrier which will allow the customer to book it once we provide them code) but connected with our inventory system. 4. We will want a page for warranty registration where customer can visit enter details of purchase with serial number to register for warranty ( in to our database) and if needed print his or her invoice. 5. Have a customer service ticketing system where when customer when login customer can chat with our support team and a ticket is generated and this communication should only be visible to the customer and our team. 6. when customer visit our page we should be able to greet them if required. 7. we have multiple warehouses so inventory system should be able to manage that bar code printing and scanning. 8. we should be able to upload inventory system using excel received with PO once items are uploaded we should get unique code for items with bar code which can then be used as stickers for identification of products and if needed we can individually edit the comments in the product and grading of product. 9. inventory system should do 1. Inventory of Products 2. manage Sales and Purchases 3. Sales and Purchases Returns 4. Incomes and Expenses 5. Damaged Products identification 6. Banks and Transactions (excel import) 7. Loan Agent and Loan Management 8. Admin and CRM (Customer and Supplier Management) 9. Customer and Supplier Order History 10. Customer and Supplier Due Management 11 Multi Warehouse 11. Multi User 13. Reports