re Layout question

Although it is tempting to reuse the same tables, In the long term I believe
you'll get more flexibility in having separate tables for
quote/orders/invoices+credit notes as theuy are functionally different and I
can almost guarantee that they'll will evolve in slightly different
directions over time. Also the reasons for browsing these tables will not be
the same, as the people using them will be different quotes: sales team,
real time; invoices : credit controllers sending reminder letters, entering
and allocating payments; orders will be used by sales and people on the shop
floor preparing deliveries etc.... they will have conflicting needs and
trying to get the ONE schema that fits all that you'll end up with a lot of
tricks, fields empty because we are in this or that format etc ... so
you'll rely a lot on the front end and your memory instead of having a clean
schema

The alternative is to use inheritance in tables but I lack experience with
that to give a proper opinion. I myself am wary of the inheritance concept
as I do not know what the long term practical implications are, even though
it is conceptually sound.

Hope this /opinion/ (hence highly subjective) is useful

Regards

Didier