Do not stay at this hotel
I was visiting Phoenix with 2 friends and found the Hotel San Carlos through a popular online booking site. I was originally pleased when I called the hotel to see if they offered any additional discounts from the online source and they knocked ~$20 off the per night price. The rating was 3.5 stars so we opted to book 3 rooms for 3 nights. Upon arrival the hotel has a very small lobby with quaint features. It wasn't until we actually went to the rooms and realized that the hotel is very outdated and not as clean as hoped. Our stay went downhill once we first went to the hotel bar for a quick drink prior to dinner and the entire lobby smelled horribly like a sewage leak. That night when ready for bed each of the 3 rooms were at least 75 degrees F with no thermostat control. My particular room was perhaps in the 80s all night with me sleeping on top of the sheets and sweating nearly the entire time. Central air conditioning in a hotel???? The walls might have well been paper since everything in the neighboring room was audible. All three of us independently opted to leave this hotel first thing in the morning upon congregating. Apparently we weren't the first people to opt leaving this hotel so they included a mandatory $50 fee for early check out but said we can dispute the charge with our credit card. 
We moved to a name brand hotel just across the street for $30 more and were absolutely satisfied.
Don't stay at this hotel. The small savings are not worth it. This is a 1-2 star hotel at best.