sorry to hear about the delays!
My experience in Spain has been that it is kind of traditional to “wine and dine” the neighbourhood folk a little and to introduce yourself and to get accepted into the community, this is quite important in small villages.
Going to the bar regularly for the morning Almuerzo is a good investment
This is quite scary when you are still learning the language but also quite harmless 🙂
After a meal and a few drinks and getting to know your face nearly everyone will become friendly and offers of help and all sorts of advice will usually follow along with a return invitations.
Inviting your neighbours in and talking about what you are doing is a good idea as well, they often will invent wild stories if left to their imagination. A regular pop round for a drink type thing could be a good investment and its amazing what you can learn. 😉
The older folk often have a very different outlook on outsiders but like most Spanish people friendly and warm to you quickly once they get to know you a little.
Regarding building etc finding out who the trustworthy local builder is and employing them to do some of the work can often be very advantageous as they will know how to get things done, they get paid on completion and hate delays.
Find out who does work for the Bar,Alcalde,Ayuntamiento etc.
I have found that getting in with the folk to be a bit of a prerequisite to getting anything done formally, the beaurocracy can be a nightmare or surprisingly the appropriate documents can get stamped and filed in seconds while you discuss the next fishing trip/barbacue/village event etc. Being formal is expected but being friendly and open is too from what I have experienced.
sorry if I am missing the scale of things and you have a large complex construction that has some real issues that need to be dealt with.
¡Suerte!