You could consider a Continuous Ink Supply System like you've seen advertised on the telly -
Melco Technologies. I got fed up feeding my little HP. I'd tried alternative manufacturer carts from Stationary Warehoue on the HP and it was horrible.
So... I've had the tanks on the Brother MFD for about a year now, and have reloaded the black ink once. Still plenty of colour ink left. I print a lot of text, with colour text, but not many piccies or things like that. Overall, I'm very impressed with the CISS system.
However.... how easy is to fit depends on your printer; the Brother MFD was a cinch, as it already has a tanks based system, and the CISS just pops its thingies into the Brother tank holes. Five minute installation.
However... adding tanks to daughters Cannon pixma was less straightforward (she gave up and called on Dad, and he wasn't too clever either, it has to be said!), and I dont actually like the way it is mechanically, but it seems to work, and the student in her will enjoy not buying carts or paying student printing prices at her institution. Hers cost her $129 whereas mine was $69, but there was a year between those purchases.