It varies greatly depending on the current finish/state of the basses condition, the type of bass (does the hole bass need finish, neck & body or maybe just the body of a bolt on)
Then you can look at what type of finish you're going too, is it a simple oil or a shellac French polish ect.
Last is it diy or are you paying someone.
All that said you're cost ballpark is about 20-2,000ish.
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