First off this hotel is gorgeous and the staff is so friendly and helpful! We arrived early and were able to leave our bags in the library while we explored the neighborhood. I will warn that there is no AC, however there is a window to open and the room stayed cool and very comfortable. My favorite part was waking up and having my morning espresso (Nespresso machine and small fridge was available in our room). Otherwise its really meant as a sanctuary to relax. The interior garden offers the sounds of trickling fountains and birds singing. Each room is different and ours (cuarto ocho) was simply a room with a bed and bathroom. Others seemed to have living rooms or were entire suites.
There are plenty of local restaurants and the Alameda de Santa Maria offers up an area to walk, relax and people watch. We saw a Zumba class, folkloric dance and several dog walkers enjoying the plaza. The location is a 15-minute ride from most touristy areas. One of our favorite finds was a biker bar across the street that had a live band - it was so much fun and the people were very welcoming.
We are planning a return trip soon and likely will return to Casa Mariscal. Highly, highly recommend it.