Hi Tracy,
I work in a hospital and we currently use Microsoft Dynamics Ax as the back-end system. It comes with GL (with Fixed Assets), AR, AP, Bank & Inventory Management modules. Its depreciation sub-module allows you to use multiple depreciation table, in case you need a different depreciation rule for your tax purpose. I believe it can also handle multi-company transactions under one system although we do not use that feature. From what I see, it is an easy to use and powerful system and most importantly a reliable one. We need very little support so far. We procured about 10 concurrent users, it is sufficient for up to 15 users unless they all login at the same time
I believe the newest version is version 2012. It may cost less than USD 20K for license and the first year maintenance but you need to pay for the implementation fee which may cost two to three times that figure.
Regards