Mahou Shoujo Lalabel (1980)

During the summer, Lalabel and her friends, Teko and Toko, arrived at the hostel owned by Teko's uncle. Teko's uncle and aunt have gone to the operation of their acquiantance, leaving their son, Ryota, to manage the hostel all by himself. Lalabel decides to help the boy out and together, all of them become involved in the management of the hostel.

(Source: Anime News Network)