It sounds like I'm not the only one who has read the stories, or had personal experience with the fact that some places/resorts in the Caribbean do require an AOW card to go to advanced sites. Actually, I've read plenty about people that weren't allowed deeper than 60 feet without one. Again, I've never heard of it in Cozumel and it's not an issue as the OP already has one.I've rarely shown a card in Cozumel, but I did in Jamaica, Bimini and in Belize. I showed a card in Cozumel the two weeks I dove with shops other than Deep Blue, and I think I showed one at Aldora, where we didn't end up diving, but did stop in and fill out paperwork. I haven't ever shown a card at Deep Blue, on the other hand, I did the OW referral, the AOW and the Nitrox certs with them. heh.I think the ballpark for a private DM is $50 for a 2 tank trip, but inquire with the dive operator. Really is worth it for one trip at least, and more if you feel like it's needed. First tanks in Cozumel are around 80 feet, which is technically considered a deep dive. Talk to the private DM about it before the dive. You don't know what you don't know, but if you ask about info specific to deep diving, you'll get it. 2nd tanks are usually around 50-60 feet and are more "fishy". As about the fish you will see and after talk about the fish you saw. With a private DM, though, you could set your own max depths such that if you wanted to go deeper than 80 feet, or shallower, you could do that, at the DMs discretion.