Differential Bearing

I am selling my car, I had a potential buyer take it to a mechanic today, and he said that the bearing in the differential is bad. He estimated it would take between $800 and $1000 to fix it, however, a friend of mine estimated about $300 to fix it. I wanted to get another opinion. I asked my boyfriend and he said he knew nothing about front wheel drive differential. SOOO, I was wanting to know what you guys thought! (Just a very lose estimate). I'm going to take it to another shop on Wednesday if I can and see what they have to say.

Any ideas would help :)

If you can get it done for $300 then shit i would do it. That's probably the cheapest i've seen to fix that. Good luck tho.;)