They never sent me any late notices, however 
they still charged me the $20 dollar late fee. 
Isn't this illegal?

Payment must be made within 48 hours.  If you 
do not make your payment within 48 hours, you 
will receive a late notice.  Afterwards you will 
receive a second notice.  When you receive this 
second late notice, you will be charged a $10 
late fee.  If you still do not pay, we will 
automatically charge your card.  If we have to 
charge your card automatically, you will have a 
total late fee of $20 added to your final 
amount. 
If you have a problem, such as being out of town 
when the auction ends, etc., please contact us 
ahead of time and let us know.  We will charge 
your card automatically and you will not be 
charged a late fee.