wanting to open a hostel in mexico - but where??!

i live in mexico city and i want to open a hostel somewhere in mexico (not mexico city).
i would loooove to open one in oaxaca or more so in san cristolbal de las casas, but there are already quite a few ..
so, does anyone have any suggestions as where in mexico is a good idea to look into opening one?!
somewhere touristy but not packed with hostels, not an expensive place for renting, somewhere to rent the
hostel and pay monthly (instead of a huge sum upfront).
also, is it better to take a business class before opening one?
are there many child friendly hostels? how do they do?
which other cities/towns around the world are good for opening up a hostel? right now i am living in mexico (i am from canada), but i am interested in the future to open others in a different country.
thanks a lot! any advice or suggestions are greatly appreciated!