I got my kit as a dummy for about $10. Powered units should run $20-30. The one good thing about these older Athearn blue box locomotives is that they were offered undecorated, which makes it easier to do your own paint scheme.
The GP38 and GP38-2 are very similar locomotives. The primary differences are the GP38-2 had a sight glass on the right side of the long hood, the GP38 did not. Filling the hole is easy. The GP38-2 also had its two fans on the top of the long hood close together, the GP38's were more spread apart. This is a time consuming task, and probably not necessary. The final difference, was the B&O selection of the larger fuel tank than the one offered on the GP38-2 kit from Athearn.
Below is a pic of a real GP38. Chessie did
not own any GP38-2's.
Dean Heacock Photo
Below is a pic of my Athearn GP38. See my B&O
4813 page for more pics.