I believe that this should be agreed with your neighbor in the sense that he will give permission for the placement of scaffolding, without which artists simply will not be able to work. You know what I mean? In addition, you will need to wash the damaged area with paint after doing all the work. I can say with almost one hundred percent probability that it will be at least a road adjacent to your houses. Therefore, I can advise you to use the services sparklewash.com , which use high-pressure washers.