I use a waterproof pouch (they sell them at CC) for money, KTTW cards, credit cards, etc. We purchased a waterproof camera bag from
amazon and a very small inexpensive Kodak camera for underwater pics and to take on CC. Easy to keep your valuables with you, no worrying. That way, you can take tons of underwater photos and delete the ones you don't like. It worked great, just be sure to follow the directions so you make sure to have a good seal on the bag. They are available for different size cameras and the one I use is called DicaPac (I don't have enough posts to post a link). At $20, it's cheaper than disposable plus developing.