When travelling in other parts of Mexico, we have hired pangas (small boats with drivers) to take us where we want to go at a fraction of the prices quoted by our hotels. We usually walked up to a stand at the marina and could hire, licensed boats. We loved this and saved quite a bit.
Does abyone do this in Cancun, or surrounds? I believe that the stands at the marina were run by the local union. There were others trying to get our business, but we always went through the union.
We are pretty adventurous and detest being run around on someone else's schedule. It looks like there is so much great stuff to do in the area - I am really hesitant to book tours.In addition, we will probably rent a car.