SO my car is a 53 plate ford focus.....I wanna know what people might think the noise coud be that its making.

its like a whining noise when I pull away slowly and when I reverse. I haven't any problems changing gears...maybe slightly tiff at times....it sounds god awful and would like some ideas so I know Im not been duped when I take to the garage!

Also how much if it is the clutch needs replacing would it be round abouts!?