I have a business idea that I have been working on. So far I haven't really gotten any negative feedback but i feel most of the feedback has been bias. I am currently trying to make a website for colleges so students can buy and sell college items with each other. I know they have a site up like that right now called Uloop.com but from what i've seen and been hearing, its not that great. I have the layouts of my site pretty much made. I want a very clean and easy to use layout which i feel i have accomplished. I was just wondering what some of the negative aspects of starting a site like this would be. I also took a survey of students at my school and most of them said a site like this would be very useful. I know marketing is going to be a huge factor for this idea working or not. But if anyone could give me some suggestions i would really appreciate it. Thank you.