The hotel has been around for years. It's a few door down from the zócalo. It's owned by the family which owns Mario's Terra Nova, the restaurant / café on the east side of the zócalo. For the restaurants and reservations for special events, I have always dealt with Yvonne, and found her very personable and accommodating. The old business card I have notes the following:
galaoax@prodigy.net.mx.
Casa Machaya Oaxaca Bed & Breakfast
[
www.oaxacadream.com]