I read somewhere that Bougainvillea is "excellent for Bonsai". However when left alone for several months, this happens: Before /After. (Though, with all those thorns, it does make a fine additional security feature. )
Fortunately, on one of our walks in the neighbourhood, we found a man perched high up on the walls shielding the enormous property of Alavaro Arzú. He was chopping away at the former President's vines and seemed happy to be recruited to help solve our vegetation problem the following weekend.
More pics of the house here.