At what point do you give up on a car?

I just got a callback from the mechanic and in order to get it back on the road it's going to be 850 for a new axle and wheel bearing. This is on top of whatever it's gonna be when the state tells me what to do about my out-ofproduction catalytic converter that's making me fail smog checks on my expired registration.

So I dunno. This could probably get as high as 1.5k. The car's from 2003