The referring link on postlets is no longer valid, so it is either not available or not legit:
A house will not rent for $750 in the Diamond Head/Waialae area. No such thing. Contact a reputable rental agent. Here are a few names
Warren Dote - http://www.billramsey.com/aboutus.html
Carl Frazier - http://cornerstonehawaii.com/?page=about
Bill Ramsey - http://www.billramsey.com/aboutus.html
These guys are almost as old as me and have been around.
Do not ever rent a home over the internet, make sure you see it first. Send a friend if needed.