All the time

I need to get some laser toner cartridges for my printer at home. I tried printing some documents today and they came out blank. Usually I have spare ink at home, but I forgot to get it this past month. I need to order a whole years worth so that I do not have to worry about it. I do so much printing that when I run out it is a big nuisance. I really need to just keep some on hand all the time.