I stayed at Casa Luna in the Chiquito Porteno room for one month (February 2020). As the name says it is a small room, but I found it extremely comfortable and perfect for my needs. The room is very well organised with lots of storage, is kept immaculately clean, has AC/heating (AC is a must in BA in summer!), and there is a window overlooking a courtyard that you can have open while you are in your room.
I also found that the room was very quiet. I would therefore recommend it as an excellent budget option for those wishing to stay in this area of Buenos Aires (for those after more luxury, there is a larger room available or the beautiful garden apartment). The house itself has everything you could need and more with kitchen facilities (including filtered drinking water on tap - which was extremely handy), a garden/courtyard, practice room and lounge. Of course the biggest advantage - especially for tango dancer guests - is the wealth of knowledge that Vicki and Rob have about BA and the tango scene, which they are always happy to share.