there are coins for smaller denominations, bills for larger ones. do your research... if you don't know the money or the exchange, you will get ripped off.
also if u go margaritaville above the bar they have $1 bills stuck to the top with peoples names and they year on amazing gota get mine up this year..
I've stayed in hotels in Cancun where they tried to charge me to change up a $100 note in to smaller notes. She soon got the box standard Ian reply but for those of you without such a grasp on the English language I'd suggest carrying taking smaller bills, nowt bigger than $50's. Ian :lol:
http://www.cancuncare.com/forum/viewtopic.php?t=37299 here it is... it took me a lot to find pics of the bills hahahaha hope it works for you