You should do the wheel bearings yourself. There's no rocket science there, and $425 is ridiculous. However, my guess is that they're fine - do them at the next brake rotor change. The only pain in the ass I had on my 124 was trying to put on a new grease cap - so try not to damage the existing one.

Have the tie rod ends checked again, unless you can feel the wear (e.g., when going over a bump sideways, like when merginig onto some interstates). If replacing them restores firmness, leave the wheel bearings alone.

The differential leak is possibly just oil from the vent. Top up the level to make sure you have enough and then watch it for a few weeks. You need the right size hex wrench.

The rest sounds like stuff to ignore until it really breaks.
Tom