I would take this advice one step further, and suggest that there is
probably a lot more complication to this application than is first apparent.
I would recommend searching for a commercial application. This seems like a
big enough industry there must be at least a few applications available.
Investigate carefully to be SURE it is specified as meeting all of your
needs (don't believe promises of "easy customization") and contact at least
a few users to see if they agree with the marketing claims. Get a demo
version of the software and test it VERY thoroughly before purchase.
As a custom developer, I think it's very hard (or expensive) for a custom
system to be better than a commercial application that's being used by many
diverse users. The commercial system developers have had the benefits of
refining application requirements both over a longer time and with more
users. They hopefully had more money available to invest in program
improvements, since they were being supported by a larger user base.
If you're doing this more for your own enjoyment and the satisfaction of
having built your own application, that's different. But if you're purpose
is the most cost-effective way to get an application that does a good job
running your business, I think you should at least start with the idea of
exhausting the commercial market before you consider building your own. You
said you were new to Access, which puts a pretty significant learning step
in the path. If you're also new to database design and development in
general, then it's a very large step. Nothing wrong with doing that
learning, but you shouldn't think it's the same as building a simple
spreadsheet.
