developing a facebook application

i need someone to develop a Facebook application like "soldsie" ,,,, please visit the app website to know how it works ,,, and how much it cost to build a similar app " [login to view URL] " ,,,,, this app allow Facebook users to buy directly from fan pages by commenting on the posts ,,,,, please visit its site and read every thing about it ,,,,, if i find anyone who can make such app ,, i will deposit the money here on this website but i wont release until i got the complete app as i got lost my money before on the millstones and i didn't get the app completed !! .... and thats how the similar app "soldsie" works :: 1-Directly monetize your Facebook page Soldsie works alongside your existing e-commerce channels, and helps you sell directly to your Facebook fans on Facebook. 2-Connect Facebook Simply connect your free Soldsie account to your Facebook Page. There is no installation, limits on admins or separate logins to manage with Soldsie. With Facebook as your business dashboard, Soldsie makes it fun to sell to your fans. 3-Upload a Product Photo Your product photos are then transformed into sales campaigns on your Facebook page --- where you can control inventory, set shipping promotions, and offer pricing specials. 4-Sell in Comments Sales campaigns become Facebook posts and, to purchase, your fans just write "Sold" in the comments. They then connect on your Facebook page, receive an email invoice of their order, and then checkout. 5-Sales Multiply As fans comment, your sales trend on Facebook as each photo is shared with your fan's Facebook friends. Soldsie works on any mobile device or anywhere your fans can see Facebook. 6-Grow Your Business Soldsie gives you more time to grow your sales with less headaches. Automatic invoices, payment reminders, inventory management, waitlists and customer communications.