what are the first clues that charles and hal do not belong in the yukon ?

Two men from the States, Charles and Hal, buy the dogs and the sled very cheaply. Neither man looks like he belongs. The camp is shabby and sloppy. There waits Mercedes, wife of Charles, sister of Hal. Buck watches apprehensively as they clumsily take down the camp, improperly rolling the tent, and loading up the sleigh unevenly. Two other men from a neighboring camp warn them that the sled is too heavy, but they will not listen.