The example I gave was one where my app was designed to replace the old way
of doing things (in this case excel). Replacing an Excel spreadsheet with a
database-driven appliation is one area where you have no additional risk of
information loss when you are running any RDBMS on the system.
Also, here in Indonesia, most of these B&B's charge less than $30/night.
Purchasing a new system (often $700 or more) is the equivalent of 23
room-nights (for a place which typically has fewer than 10 rooms). Used
PC's are out of the question because usually they have hardware issues, and
so the cost savings would be marginal.
Please remember that the economic tradeoff of whether to buy an additional
system varies quite a bit around the world. For this reason, I decided to
build my application to be platform and database agnostic, supporting both
Firebird and PostgreSQL.
Best Wishes,
Chris Travers