Seeking advice from kitchen sink experts

Hello
I am a member of this community who usually just lurks.
I visited my father's house today to drop off his medication, and the caregiver who visits for three hours a day mentioned that water keeps leaking from under the sink, causing inconvenience.
My father lives alone in the countryside, and it seems like it's time for a replacement. I want to get it replaced for him, but I want to avoid getting ripped off and pay a reasonable price. How much would be appropriate?
I measured the dimensions, and it is about 3m × 2.3m.
What would be a fair price range?