I am rationalizing my business database to incorporate all addresses
(customer, supplier, reps, contractors, personal, freight etc) into the one
table system.

Given this, is it possible to do the same with the
Customer/Supplier system, so having only one Invoice form and using it for
customers (invoices) and Suppliers (purchase orders) and using a filter to
restrict which address name is selected?

I cannot foresee any problem but I
would like to know of any. Please help, Frank