Accounting/inventory systems

Can we develop difficult accounting/inventory system and use PostgreSQL  for
server. We will use MsAccess for client.
We have to choose between:
MySQL PostgreSQL or another server .
Does some company use PostgreSQL  for these purposes? My be there are some
commercial realises of accounting/inventory programmes which use PostgreSQL ?
Does somebody know some REALLY working accounting or inventory system on LAN
(not via Internet)??? - where server is PostgreSQL .Because I have feeling that PostgreSQL
is used only with regards to Internet.
Any additional information will be highly appreciated in our hard decision
process.
Thank you!

Because I have feeling that PostgreSQL  is used only with regards to Internet.