Setting up a new QuickBooks-POS-12 installation for a client today and learned that when Intuit means their POS application is peer-to-peer network ready, they truly mean it, peer-to-peer NOT client-server. Make note, network admins, the first machine you install QBPOS on, which will be a desktop(most likely) WILL be the Server/Host, no if and buts, nor changing it, unless you backup move, uninstall and install at another desktop. It is not like the network version of QuickBooks, where you can store the DB(database) file only, on a server and share it from there.
QBPOS is hardcoded and you cannot change the default location of the POS DB.
QuickBooks POS database location