Estela's place is just as expected from the pictures and the listing. It's small and cute and available at a great price. Really the best part about staying here was Estela herself, who is so nice and helpful, and the location. It's super close to Retiro park (only about a 5 min walk) and close to the Ibiza metro station (about a 2 min walk). There are also lots of cute restaurants, a bank, and an Orange phone store all within a few minutes' walk.
Something I should mention is that if you don't like cats or dogs, don't stay here! There are lots of both and while Estela does keep them out of your room, they're definitely still in the apartment. Also, be sure to message Estela for the full address of the place before going as it doesn't pop up when the reservation comes through.