Once you connect POS all your inventory is kept in POS and not in QB anymore. Thus, if you want to sell services or non-inventory items you could bill them through QB, but if you wanted to track inventory you really need to run it through QB POS. We have both wholes and retail customers and run everything through QB Desktop Premier. We sent out our commercial and/wholesale customers invoices and statements from QB after we import the data from POS into QB. Hope that helps.