I was chatting with a friend a few days ago and we were discussing where we were living. What I really mean by discussing is we were telling horror stories of choosing the wrong place to live. He had some terrible maintenance at his place, got hustled, and more. I got held up at gunpoint a week after moving into my new apartment. Two weeks later the tags on my car were stolen. One month later a guy tried to force my door open (thankfully I had locked it).
Thus came my idea. Facebook has a large population of college students. College students tend to live in apartments. Why not create a facebook application that allows students to share what they know about the places you can live?
You could use referrals for monetization. Create the option for students to enter in an e-mail as to request more info (or something less intrusive). 10 students say Amazing Apartment Place is the best place they’ve ever stayed? They enter their e-mail and request information. A month later they sign the lease and you get a piece. For something with faster turnaround revenue, you could do $x amount per number of requests.
Yum. Comments. Tasty!