The road only takes you as far as south Habaneros area, just north of Sapphire Beach. Then it is a 4 miles drive on the beach to TBR. It's up to your rental company, because if you get stuck somebody has to rescue you and the vehicle. The water area north of Sueno del Mar is the Bacalar Chico Marine Reserve, no take. Anything. And the beaches are some of the last nesting ground for turtles May-Nov, so proceed with all due caution. Hence sometimes the taboo label. A proper road off beach would be welcome for these reasons.