The best and more benefit way to get to Costa Calma its to rent car in airport .

If you will do it in advance you can get the most low rates: up to 80 euros per week.

To rent car is the best solution which I can recommend, because you can explore whole Island visit all the beaches and can feel free at your shopping.

If you reach by bus from the airport:

The best option will be to get on the bus No. 10 which goes from an entrance from the airport and will take you to Costa Calma, for 1h 30 minutes. Fare about 8 euros for the person. The bus stops in Costa Calma on a circular outcome opposite to Furteventura Playa hotel, it is your stop.