I have a small book shop and have been keeping records the hard way (Excel). I'm trying to create a database to track my purchases and sales and be able to pull out reports of inventory on hand. I've got most of it figured out (on paper -- haven't gotten to the creation part yet), but I'm stumped by one thing. I sometimes order lots of books in bulk (50-100 at a time) and sometimes come across deals of single books. I'd like to be able to create reports that show the unit cost of each book and what I've sold it for so I can do a P&L on individual items to see if it's worth my while to continue to buy lots from certain sellers. Do I need to create two tables: one to enter the purchase of lots and then to allow me to enter each inventory item separately and another to list individual books purchased? And if so, how do I link those so that my inventory listing sees everything that's still available? Maybe I'm tryng to make this harder than it is, so any help will be much appreciated!