I have a custom object used by our health team to track pregnancy data/ post natal records.  Our health team will sometimes provide our clients with supplies (we are a charity) and we would like to track what supplies are given out.  I have successfully created a junction object which has allowed me to show the 'products' related list in the health custom object.  So our health team can add a product to the record.  Is it possible to allow them to also specifiy quantity?  I am not able to do this - no field for quantity appears as an option.  They can potentially click to add product multiple times if needed but ideally we can specify quantity.  Ideally I'd also like to only specify certain products- either by record type or by price book.