Virtuemart website - modifications + resolving the issues

WE have Virtuemart website and on this project, we have used other PHP developer who was unable to make some modification or he didn't complete them. Registration fields should be like we want (first and second name, user name, phone number, and email) In the cart final step this what is in the user details should be auto-filled with user information (fields are in step 1 listed) Price should be hidden in the cart Order email doesn't arrive to the admin or user. This should be resolved Order email layout should be very simple with user fields (first and second name, user name, phone number and email + comment if he provides him at the last step). Everything should be removed except the name of the products (this means that all prices, quantity,....should be removed) After the last developer work when you go to the registration if you want to confirm your registration it shows the error.