SubNavigator:
First, if it has been 10 years since your last dive, I HIGHLY recommend and encourage you to do a refresher course. In fact, most reputable ops will require this after a 10 year haitus out of the water.
Del Mar and Dive Palancar are now one in the same. Dive Palancar bought Del Mar awhile back. You should be fine with those options without dive reservations. They have many boats and big boats if that's what you want.
I posted most of this info in another thread, but since it applies to you as well, here it is again
If you are planning to dive with another operator (offsite), then I highly recommend that you contact one or several and make reservations. Dive Palancar is a fine operation, and IMO one of the better of the big operations. However, if you are looking for looking for extended bottom times and small groups, they might not be the right choice for you. In that case, I would suggest researching several other operations and find out who has the services/options you are looking for. There are MANY favorites on this board and many good operations, the key is finding the one that suits yor needs. Any of them can pick you up at Casa del Mar provided that the pier is rebuilt by the time you are there.
Credit Cards on the Island
No one on the island accepts Discover and very few accept AMEX, so you might as well leave those at home. Establishments that DO accept credit cards will usually apply a surcharge because the banks in Mexico charge outrageous merchant fees...this makes accepting credit cards for small businesses almost unrealistic. This is why you'll find that smaller restaurants and businesses just don't accept them.
Dollars vs. Pesos and the best way to convert
DO NOT convert dollars to pesos at the airport in the states before you get here...you'll definitely get a lower exchange rate (i.e.: 9 pesos to the dollar vs. 10.44 pesos to the dollar). I do recommend changing some dollars to pesos once on the island however, as you will get a better exchange rate that way. Although everyone will take dollars, the exchange rate in most places is at a set rate, and it will always be higher then the banks and change house rates. For example, they will have a set rate of 10.5, when the real exchange rate is 10.35. On $100 that costs you an extra $1.50. While it may only be a few dollars here and there, that does add up over the week. So, it's always best to pay for your meals in pesos, hotel in pesos, and souvenirs in pesos. Most dive shops I know of, will give you the real exchange rate for whatever it is that day on the island.
There are change houses ALL over the place and they are almost all owned by the same person, so no need to shop around for a change house with the best rate...they're all the same. The banks are typically the same rate as the change houses, and you will have to stand in line forever. The exchange rate is usually a point or two lower than the actual market rate on Wall Street.
ATM Cards in Cozumel
There are also ATM machines ALL over the place and that's how you will actually get the best exchange rate, because it is YOUR bank setting the exchange rate, which will be the actual market rate for that day, again savings you a point or two on your dollar.
Most ATM machines have a $3000 pesos (currently $287.25 USD) transaction limit, but there is no limit to how many transactions you can make. Some banks (Banamex and Sandafer Serfin and Banorte) have $5000 pesos (currently $478.74 USD) transaction limits, again no limit on how many transactions you can make. So your maximum daily withdrawal limit is set by your bank, not by the bank machine in Mexico. You can always request that they increase your daily withdrawal limit for your trip and then change it back when you get home if you want.
One more thing about transaction fees for ATM's in Cozumel. Remember that they operate with pesos in mind and the $ sign is also the sign for pesos. So, when they ask you if you agree to the $7.50 transaction fee, that is 7.5 pesos, (78 cents). The most I've seen on any machine in Cozumel is $15 pesos ($1.56). YOUR bank in the US however may charge you an out of network transaction fee...for example Wells Fargo charge me $5.00 USD for every transaction. However, if I use my Bank of American ATM card at the Sandafer Serfin, I am only charged the $1.00 fee for the machine.
