Add 4 Features onto a Shop

Needing 4 Custom-developed Features added onto my Shop Script coded in php: 4 Custom-developed features on the script: 1) Reverse auctions: Normally only sellers can create Auction. I need the opposite too, called Reverse auctions: So, targeting buyers can create reverse auctions to invite lowest bids from sellers? This is opposite to forward auctions above. The seller's bids to be shown as lowest bids at the top of the page, in ***ascending order, with highest bids at bottom, or subsequent pages, so buyer can pick the cheapest price at the top. 2) Forward auctions: I also like to have forward auctions, so sellers can create auctions, for buyers to bid. Buyer's bids displaying: highest bids at the top of the page, ***in descending order, with lowest bids at bottom, so seller can select the highest bid at the top. (This bidding is just an extra thing to the current direct store sales, ie "Buy Now" on the script.) Before Bidding, put Recommended Bidder (by lowest price), unless it is not least expensive but had plenty of reviews, at the Top of the Page. After Bidding, put Awarded Bidder at top of the page, when Awarded. 3rd, there is already a Dashboard. On the Dashboard, add a News feed of the Bids received and Recent Project (Follow this Freelancer.com's Dashboard page structure as a guide). 4th, Add a Private Message Board, so buyer and seller can renegotiate auction price. (Follow this Freelancer.com's Private Message Board structure as a guide). Final note: No Advance Release of Milestones. 50% Milestones uploaded for creation of First 2 Features. When proof of that is shown, next 50% milestone will be uploaded for creation of 3rd and 4th features. Both Milestones released in entirety only at conclusion of project when delivered to client side. When you bid, you implicitly agree to the terms and conditions above.