Adding Facts to Transactions

I work for a medium-sized grocery retailer, and the business folks would like to evaluate the end-to-end view of each item at the sales transaction level for several different projects. Currently, we are storing the Item, Quantity Sold, and Sales Amount at the Point-Of-Sale. However, the business would like to add Regular Price, Actual Cost, and Supplier for each transaction line. What is the best practice approach for doing this?

Thanks for your help!