It is often unbelievably low rent that first attracts victims of a rental scam. The scammers count on the victim casting aside common sense in order to get an unusually good deal. Don't be fooled! Look carefully at any rental offering that is out of the norm in any way.
Definitely a scam. To make sure that they have the most complete list of available properties Trulia gets data from many different sites. Be especially wary of ads originating from sites that allow anyone to post (this one came from rentalads.com one such site).