I purchased what was billed as a snorkeling tour to see turtles and potentially a dugong at Abu Dabbab for me and my girlfriend. The site included an itinerary, but when the day of the tour came, we discovered it was not really a tour.
For 30 USD, they drove us to Abu Dabbab from our hotel, about a 10-12 minute drive, each way. On top of that, it's an additional 7 Euros per person to enter the beach, paid on arrival. Then it's additional fees for snorkel masks, flippers, and wetsuits, if you don't bring your own.
The taxi driver dropped us off and left us to our own devices, only to return at the end of the day.
The beach was great with gorgeous coral, and we saw a couple sea turtles. But this tour was unnecessary. Just get a taxi there. Unless you're very far away, it'll be cheaper.