We did a major construction project at our house last year. Three massive terraces, a lap pool, serious stuff that took 8 months.
Our main guy was retired from the city where he drove an ambulance for 35 years.
We had to get two "permits." One because they had to have a backhoe come in and stay in the back for several days, that cost 2,000 pesos as long as all construction materials stayed in the garage or behind the house. The second cost 3,000 pesos because we had to have the Putzmeister (cement pumper) come in and pour the pool. The mayor owns Putzie and the three cement trucks that supplied the material for the pool.
We were happy it was so easy, but would have been kind of willing to spend several months getting permits, maybe. ESPECIALLY if we had know up front that permits were going to be less than "legal."