Perfex CRM Module Customization

Hello, I have a module called Eshop for Perfex, In this shop i want to add a coupon code option, where we can create coupons and offer to customers, And also after the order is placed, We want to add a option like Fiverr to ask questions from customer about the services they want, or to provide their logo or other information. So add a section in Eshop module called "Coupons" that we can add new, or remove the existing one, once adding coupon we want to add percentage or amount. Next add a section for order form, which should be different for every product, and we should be able to pick different forms for different products, the form should appear after customer pays for the service, so we can add questions based on the product. How long does it take and the cost please?