In this climate i would say collecting is not best at all,if you have custies that are a bit strapped for money give em a bit of time to pay if you ask me.If your knocking on the door every month and a month soon comes round they will be more inclined to say can you take me off your books as i can`t afford it,i put tickets through and never badger them to pay on time i find this works better,most businesses give you 28 days to pay.If your wanting to look more pro this is the way to do it.