Hi haribo,
I like the idea a lot. Maybe you could require everyone with an account to have to register a skype name or Facebook video name or something. I just read a newspaper article where a police station is letting people from craigslist come to the police station to make mutually safe transactions so there is a market for making the classified market safer. I might even add an escrow service if you can and also do not make it local but make it global where shipping is available. I really do like the idea of a video based marketplace and I hope you go through with it. Maybe make and Ebay like auction site but to post a product you have to have a video featuring it. I do think you are onto something.
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