First, I would like to express how sorry I am, cmzee and the rest of your family and her friends for having to go through this very difficult time. My thoughts and prayers are with you.
One thing that keeps sticking out to me as I have been following both Rachel's and Sarah Stern's disappearances is the wording used in the news links cited. While it has been repeatedly stated that Sarah's car was found "on" the Belmar bridge, it has been repeatedly stated that Rachel's car was found either "near" or "by" the Driscoll bridge.
Perhaps, I'm looking too much into this but it has made me very curious. Being from the area, the Driscoll bridge is a busier bridge, especially at the time the cars were found. Not being found "on" the bridge increases the likelihood of a possible abduction, especially considering the seedy areas near the bridge.
I would also like to know if the car was operable or if there was any damage.
Just my $0.02...