Laser toner $$ Savings
HP and Lexmark will hate me for telling you this. You can often get your laser printer back to printing BLACK again if you tap the cartridge from end to end with a heavy pen or small ruler.
Tapping frees a lot of toner stuck to the inside of the cartridge and so allows your printer to print many more good copies before exchanging for a new one.
Low overhead and living frugally keeps money in your wallet longer. Now where the heck can I get a good electric jeep. TG