We have met Ulises briefly, he does not live in the apartment, his mother does. She does not speak English but it was the problem at all. The apartment itself is quite old so I imagine it is hard to keep it super clean. Some places need refurbishment.
The location was great, very close to metro station (like almost in front), about 5-10 minutes walk from Plaza Major. There were coffee-houses, breakfast places or tapas bars all around.