I'm trying to get flights booked, but have one question... With check being at 12:00 p.m., can you still use the resort (pools, bar and etc) if our flight doesn't leave till 5:00 p.m.?
Yes, you just have be out of the room and they will keep your luggage by the front door until it is time for you to leave.
Just did this on Sunday. If you ask they may let you keep the room for a few hours past checkout. At checkout they cut off the wristband but give you a checkout receipt slip which lets you use the facilities until you leave, drinks and all.
Also ask a Cancuncare friend if they'll stash your bags in their room. Wish I'd thought of this last trip!