As mentioned above, the frame needs to be checked. A lot of the suspension will probably need to be replaced. Lots of body work to be done. Anything that sits low on the car (eg, engine, transmission, exhaust) will need to be thoroughly inspected for damage.
Unless you REALLY trust the shop that will do the work, I suggest pushing to total it. I trust the shop I use to give me an honest assessment of damages and whether or not it can be fixed right - a lot of shops aren't quite so honest.
