We did the same for a company "FD" they were 90 + due, and we hold on their orders.. We contacted a local attorney 2 blocks from the client's address.  When the clients found out the attorney was 2 blocks away, they overnight us a check $2500. they still owe few orders, and they know we will use the local attorney if they are behind 30 days.  Paying for copy cost and employees is hard enought, if clients do not pay you on time.