Conclusion: The neighbour is someone who lives close to you, which includes houses that are next to yours, according to scholarly consensus. With regard to anything beyond that, reference should be made to custom. With regard to the view that all the people of a quarter (or part of a city) are neighbours, this is the view of some scholars, as mentioned above (Abu Yoosuf, the companion of Abu Haneefah), but quarters in the past were small, hence he said: If they all pray in one or two small mosques. And Allah knows best.