Green’s Dictionary of Slang

it will cost you something, i.e. don’t ask for favours, but most things can be done – for a price.

1984		Partridge DSUE (8th edn) 603: cost yer! [...] orig. (1920s) prisons; in 1970s gen.
1988		InfoWorld 27 June 78: And I know something about some other new computers, too, but it’ll cost ya.
1992		J. Harju Northern Reflections 110: I can put a new one in, but it’ll cost ya.
2004		W. Self Dorian 172: It’ll cost ya. — Of course.