plog said:
3. Reference number goes away. It will not exist in a table, it will exist as a calculation wherever you need it to. Most likely in a query, where you will then use it in reports.
Just to be absolutely clear: This statement, though probably true for your situation, in fact could be true or false DEPENDING ON INTENT! Since you have another way to link dependent table data to the independent table (or, if you prefer, child to parent linkages), it is probably true that you don't need it.
I'll spare you the full writeup I usually give for people in the planning stage. However, I will add to the consensus that right NOW is the most important part of your process - designing and THINKING about the design. Take good notes. Make drawings of data flow. Whatever works for you to help you think about something and REMEMBER your intentions, do that. Build yourself a road map (logically speaking) of where you want to go and what you want to do.
This might sound like a joke, but in a way it is not: Treat your project like you were planning a really great multi-stop vacation with your favorite partner. Plan it out to know what you will see and how you will get there. Almost like a vacation triptych that you might get from a commercial travel service. The idea is simple: If you don't have a good road map, (a) how will you get where you want to go? and (b) how will you be sure you got there?
Nicklaus Wirth, the "father" of the PASCAL programming language, was once quoted as saying that 80% of all programming problems originate from bad data layout. So spend some time up front to be sure your data is laid out well. And good luck with your project.