Build a Steam-connected marketplace website

I am looking for a web developer to build a marketplace website with CS:GO inventory items (skins). The user needs to be able to log in to his Steam account and select the items from his inventory he wants to sell. A bot will be the medium of the transaction - meaning the seller sends his item to the bot, the item appears as up for sale on the website. It is stored in the bot's inventory until someone buys it - the buyer gets his item, the seller can cash out money (through a payment system of my choice). The trade needs to be secure - a randomly generated security code displayed in the trade offer would work best. The item's picture and float value (condition of the item) needs to be displayed on the website and the user needs to be able to inspect the item in-game before buying. The website needs to look clean and simple. Please send in your offers and examples of previous work. You will need to sign a non-disclosure agreement. Further details upon contact.