In Costa Maya you can get a cab to Mahahual. It was $4 one way. (I rode with one other person.) I walked the 30 or so minutes back to the port. Maybe there’s a family deal. The cab dropped us off at one particular spot, with food, beach and lounge chairs, but I’m all about free/cheap. (There’s a big pedestrian walkway that parallels the shore, with lots of little beachside areas with food for sale, chairs for rent - or for use with food/drink purchase, etc.) Toward what I assume is the southern end there is plenty of free beach. You can see the ships and lighthouse from there. Inexpensive massages are also offered at various places on the beach. Water was nice last week, and snorkeling wasn’t bad (and pretty close to shore).