Magui's apartment is quite a unique experience, I highly recommend it if you want something different from a sterile, impersonal hotel. The vintage decor is one-of-a-kind, and it matches well the age of the building. The building key is indeed tricky, so you should definitely have someone show you how to use it. My stay in Valencia was disrupted by personal problems, and Magui was very understanding and kind, I am very grateful to her for this.