The Hostel is directly where the Kiteschool is, you can jump from your bed onto the board. 

Bed in the big dorm (8 Beds) aprox. 17 USD

Bett in the small dorm (4 beds) aprox. 24 USD

Private room aprox. 70 USD

reserve!

Within walking-distance to the school you find many airbnbs and a few Hotels:

1-Star: Manzanillo Beach Hostel 

2-star: Hotel Aria 
4-Star: Boutique Hotel Kohsamui

5-Star: Hotel Karmairi

5-Star: Hotel Estelar 

If you don't want to miss out on the lively nightlife in Cartagena, you can choose one of the hundreds of hostels and hotels in Cartagena Centro Historico and head to the beach in the Pure Kite shuttle.

Here are a few tips from the young and active Getsemani district:

Casa Ebano *** (nice hotel, cheap and with warm water (rare) and Rooftoppool)