are u printing colour photos or documents? My personal experience for A4 colour photos is $3 to $4 per photo.
1 set of 6 colours inks is not enough for 50 A4 prints.
I think you have mentioned your lens is still working, other than "tight zoom ring". So I don't think there is a need for repairs.
Your might as well use until it is "fully spoilt" before sending in. I think the repair cost is still the same:think: