When HP sell you a new printer (J4524) they only give you starter cartridges with it which hold a very small amount of ink in them Hp 901 black 4ml and the Hp 901 9ml colour cartridges. I was using about 3 black and 2 colours cartridge per month and it was costing me a small fortune. I later found out that Hp do a higher yield versions of the 901 black cartridge which cost only a few pounds more but hold far more ink in them than the starter cartridge which I was using before. What you need is a HP 901XL on the black which hold 14mls of ink rather than the 4mls of ink that is in the 901 starter black cartridge. HP don't make a XL version of the colour cartridge. I can even go one better, I now use a company called advantage online who stock the Hp 901XL originals plus do a British premium compatible 901XL bk and 901XL colour cartridges which hold 20mls black and 21mls colour. I have used them a couple of times so far and have been quite impressed. I hope you don't fall into the Hp trap of selling a very good printer (Officejet J4524) at a very cheap price and then trying to charge you load of money for starter cartridges.