Electronics

[lhs43]

I recently purchased my first printer, an HP Deskjet 1056. It uses separate black and color ink cartridges. The kind I need to buy is HP 61XL. I have 2 questions:

1) This XL cartridge has a capacity of 480 sheets. I've only had my printer for about 4 months and have fairly low usage. I don't use it every day. In fact, I have to make sure to print a couple of sheets each week so the ink doesn't dry out. No way, no how have I even printed 150 sheets and the "low ink" light is flashing. Anyone have a clue as to what I might be doing wrong?

2) The black ink cartridge costs $27.99 pretty standardly across the board, even at Costco which surprised me. Amazon is $29. There are a couple of sites that sell it for $15 or so. (CompandSave site). Would you trust a site like this or would you recommend that I just purchase the cartridge at the going rate?

TIA!