You do get change when you buy them, but only if you went in with enough $100 bills to fill a airline baggage bin. Then you need the same again for the accessories, like leads, batteries, pressure sensors ( oh, you will need 4 bins of those hundreds though for the pressure sensor if you want anything above the basic).
Bring in a few gold bricks, it will be easier to carry. 40kg will just about cover the full suite.............