after an year of travel from US to Argentina by car,
my family is temporaly setteled in Buenos Aires.
it's partly because we wanna see more of Patagonia.
and i wanna travel by horse this time because i want to travel very slowly and it will be better to see the beauty of Patagonia.
Has anyone done this or has some informations about it? like permission matter, if i can get into the city or town,
the price of horse, etc.
This will not be easy. As you probably know, pretty all land in Patagonia is privately owned, and most land owners do not want people on their terrain, period. Planning this on your own is out of the question, unless you want to use the roads.
However, I guess there are specialised tour operators that cater to those interested in horseback riding, so you could probably book a tour of sorts. It won´t be cheap, but maybe it comes closest to what you envisage.