Very nice, clean, quiet, secure place! I stayed there for one night on Halloween to go to a concert and it was everything I needed. The room was the perfect size for me, and though I didn't have my own bathroom there was one right outside of my door, and a bathroom w/ a shower another door down. Everyone there was very quiet and respectful, including Guillermo himself. Upon arrival he welcomed me and showed me around his lovely home, and was very open had I had any other questions. The thing I liked the most is that his place is electronic - there is a key code to get into the front door, and each room has it's own key code as well, so you don't have to worry about carrying around and/or losing a key.
His home is in extreme walking distance to downtown. I would say it was maybe a 15 minute walk? The neighborhood was nice and his home is right next to a cute park that you walk by on your way to DT.

One other thing to note is that I had a few questions before booking this listing and Guillermo was super quick to get back to me! He worked with my on my ETA to his home, and once again was very quick to respond once I had landed from my flight.
Oh! In the morning he had toast and peanut butter and coffee and bananas in the living room for us :)

I would 100% recommend staying here whether you are here for business or leisure. And fellow female travelers, rest assured this is a safe place for you! I will totally stay here again if I come back up to SJ :)