OpenCart Development - eCommerce Marketplace

I already have an OpenCart store built using Waabay's MultiVendor module. Vendors can login to manage their own stock and orders. Payments are made automatically via PayPal Adaptive Payments. I need to below functionality built onto this existing module:

- vendors add their own postage prices (multiple per geo-zone) which are listed per vendor on checkout and also sent, with product payment, via PayPal Adaptive
- vendors are able to manage discount codes and coupons which apply to their own stores only
- vendors are able to set their store in 'holiday mode' if they are unable to fulfill any orders
- vendors can easioly make a widget to sell products on their Facebook page
- vendors are able to purchase (via a restricted category) spaces on a featured products carousel for selectable products of theirs
- vendors are able to purchase (via a restricted category display ad spaces which will be shown around the website