The thing is that in this part of Andalucia (Cadiz), the local councils are issuing licencias de obra for naves with the full knowledge that a house will be built.
They are doing so because the Junta will not give permission to build on rural land. We have a small olive farm of 42.000 m but have been refused permission to build a house, not by the council but by the Junta. They want to see income derived from the land that will support a family before issuing a favorable report to the council.
Thus, the only way to achieve a new house on rural land here in Cadiz is to build a nave. The locals have always done it to avoid taxes and professional fees.
You’d be hard pressed to find a legal house here.