Sizes are NOT true to description

order a pair of sweatpants for my son for Christmas - size medium - they were SO SMALL they fit like a pair of tights. Contacted site (thru amazon) and was told I had to pay to return them, pay a restock fee and/or pay to have a larger size shipped. I used THEIR size chart to determine the size I ordered!!! Not to mention they asked that the money be either cash, check or money order - WHO DOES THAT???? And they want it shipped back to a P.O. Box.
Contacted Amazon regarding this issue - will see what they say. Also found the same sweatpants for 1/2 the price at another site.