Casa Santo Estevo

We cannot answer your question based upon personal experience.
You bought an up and running Casa Rural because an Imobiliaria (estate agent) advised us that the rules are complicated and written in Gallego or Castelaño. Which at the time we did not speak well enough.
However we do know something about the process was and we have all the paperwork associated with the registration of the house.
Basically you have to draw up plans and have them approved by the Xunta.
The previous owners used an architect and an administrator to help with the process. Nevertheless they said that they still had to run from one office to another for various approvals and paperwork stamps. If not the process of approval could have taken a lot longer. This bit of information was told to us after the purchase so it was not said as though to put us under any pressure to purchase the house. The best advice is to find an English speaking administrator who will help you.

If you recall we gave you some information previously about the paperwork in response to your question about B&B regulations. So your house will have to conform to all of that…. and more, if you know Spain.

We are now in an association of Casa Rurals which helps us understand any new regulation being applied and they also help us get guests into the house with advertisements etc. Hopefully there is something like that near where your proposed house is located.