Regarding the renovations it really depends on the extent of the work you want to carry out.
Different work requires different licenses. Some licenses can be registered and received in a short space of time, but more detailed work, especially work that effects the structure of the building require detailed permissions. These take time to plan and process. They are granted by the local government or ayuntamiento, they also need to be sent to and authorised by the COAC. The architecture collective.
Regarding tradespeople, as in any city in the world. There are good and bad workers. Obviously if you haven’t worked with them before it’s difficult to initially evaluate. However, references and examples of past work and portfolios are always a good start. Contracts are also important with penalties for late completion.
Architects, however, did surprise me when I first started here. In the UK it is a highly regulated industry. I therefore presumed the standard would be equally high and an architectural education would guarantee a high professional service. However, I realised that there was an abundance of architects and not all were of a good professional standard.
Regarding a lawyer, I haven’t heard of DiG advocats, but if people are recommending them, it’s usually a good signal.
I do have a trusted abogado that I use which I can recommend. I don’t think he would appreciate me putting his details on a message board, but if you wanted to email privately we could discuss the relevant details. (I will be out of my office next week, but returning w/c 22nd July).