Front End
 

I have a klunk noise when you put on the brakes. With someone walking next to car the front wheels move backwards a little when brakes are put on. Not sure what to look for. How much to Fix?

Obviously can't be exact from limited info. ;also you don't state what car you own. I would say worn bottom ball joints and would advise you to have this checked urgently,as if the movement can be seen the wear is advanced and your suspension could collapse .
Geo.

I would say the most common cause of forward backward movement on braking is some manner of lower control arm support. The answer would be distinct for each model.

Front end
 

Thanks for the help, My car is a 1984 300SD
I have no tire ware and the car goes straght down the road just has that klunk when brakes are put on.

Sounds like a ball joint to me (lower). Is it coming from one side or from the middle? If it is coming from the side, try this: jack up the front end on the side in question (not undere the control arm, but the body of the car) untill the wheel is off the ground. Then locate the ball joint and pry on both sides of it with a prybar of some sort; if there is play, DO NOT DRIVE. Ball joints usually run around $200 plus parts ($20-$30). Tell-tale for the BJ will also be a squeek when you rock the body up and down from the fender area. Check that, and then post your findings. Have fun!