max shopkeeper payout

The shopkeepers vary greatly in the max they're willing to pay.  I say 
enough of this madness.  It's something that players have no control over!

It's a bit of utter randomness.  Not fun!

Let's make sale prices depend on charisma, which would make that stat more

useful for a change!  This is something that could be added to the game 
quick and easy.  The game is undergoing some pretty meaningful changes as
it 
is.  Let's just add this one.

Does anybody think the might be worse for this change?