2004 Dodge Stratus Bad Brakes?

I recently took my car to get a second opinon about a leak in the transmission seloind pack that the dodge dealership said I needed to replace/and I had the brakes inspected and she said that they were okay(which I did not believe b/c I can feel vibration when using the brakes). And this independent mechanic said that I could be resealed, but the problem that I needed to focus on was the front left brakes. He said that I would need to replace the caplier and if one gets replaced then both need too? He said that it would be good to also get new rotors on both the front brakes, also? So my question is I know that I need to replace the left rotor b/c the rotor and the caplier are almost beginning to start touching one another and that isn't good. Should I just replace both caplier/rotors? Is there anything else that should be replaced along with this fix? What should I do? He said that the money i'll be paying out is about $627.36! Can it be a little less if I just had my dad do this for me?