Hey crusader. Just got back from Mr. Sanchos last month. I will try to give you a good comparison between the three.
Since you have three teenagers, I would suspect they are going to be happiest at Playa, since the non-motorized water toys (the iceberg that you climb on and then fall into the water, hammocks etc) are included in the $8 per person admission price. The taxi is $12 for a family of four one way. (Sorry we have never priced it for a family of 5) Since you don't drink that much, the $8 general admission would be all you would need. Be aware, the umbrellas may be extra. The "all inclusive" is for the drinking crowd. The pros is that there will be plenty for your teens to do. The cons will be if will probably be crowded and the crowd will probably be the drinking, partying kind. We have never "participated" at Playa, as the time we were there, the weather prevented any swimming (red flags) in January. They did allow us to walk around a little for free. We just walked on down to San Fransisco beach (which is free) and watched our boys play in the sand. Like I said the weather did not allow much more than that.
Mr. Sanchos is free, but there are no non motorized toys. They do have jet skis that you can rent for $55.00 cash for 1/2 hour ($60.00 is your charging it), horseback riding, ATVs (sorry we did not do those...so I don't know the prices.). However, it costs nothing to sit under their covered tables and relax in the shade. A frozen marg is $4.90 and bean and cheese nachos are $5.50. Both are wonderful. I am not a big drinker either and they were just right. Taxi for four is $14 one way. You would love this one because it was quiet and relaxing. All the "motorized" activites were far enough away not to bother you. But since I don't know the energy level of your teens....they may not be entertained enough.
Nachi Cocom always calls itself a "free" beach BUT they do expect you to eat or drink at least $10 per person to use their facilities. I am not sure if you pay it upfront and then they credit you as you consume the food or drinks. Nachi Cocom is also right down the beach from Mr. Sanchos.
All three have restrooms, showers, pools of some sort...although Nachi boasts it has the best pool. There is a Web Cam that shows the entire Nachi facility...but I can never figure out how to paste in on this site. I have never used the "restrooms or showers" at any of this places...because my kids aren't "all day people". They like to get there about 9am...play for a couple of hours and head back to the ship. The only place I have had the food and drink is at Mr. Sanchos...but I am sure all three places are fine.
Do not worry about getting a taxi back to the ship. We have always found them lined up (even as early as 11am) to take us back...just like they are lined up at the dock.
Also remember that all prices at Mr. Sanchos is in pecos. So when you see a drink that costs $49.00 (it is about 10% in American). Have a great time. Cozumel is my favorite place to go. They have always made me feel very comfortable and safe.
Cozumel also has a putt putt golf course downtown (about 4-6 blocks) off the beach from the square...that is very challenging. It is owned and operated by an American couple. Sally is a sweetheart. And it is neat getting their perspective of living in Cozumel.
