I stayed in this "Casa Santiago" apartment for two weeks in April 2011 with my wife and another couple (my friends).
Firstly, you must decide if El Cotillo village itself is good for you. It's small, charming village with two very different beaches around and excellent views to the ocean, especially during the sunset. We enjoyed walking around, dining in the restaurants right near the ocean, resting in lagoons to the North or exploring the rocks around the long beach to the South.
On the other hand, if you want to shop, exchange money, get some excursions - you have to drive elsewhere. Bus service is excellent: you can get to Corralejo each hour, but hiring a car is more convenient. Also you shouldn't expect to see any youths in El Cotillo other than surfers who spend the whole day either sleeping or riding the wave.
Now, back to the apartment. It's located conveniently: near the middle of the village. Village is very small, so there is no much... more