Amr bin al-Sharid (may Allah have mercy on him) said: Al-Miswar bin Makhramah (may Allah be pleased with him) took my hand and said: Come, let us go to Sa'd bin Abi Waqqas (may Allah be pleased with him). So I went out with him while his hand was on my shoulder. Then Abu Rafi' (may Allah be pleased with him) came and said to al-Miswar: Will you not tell this man - meaning Sa'd - to buy from me my two houses which are in (adjoining) his compound? Sa'd said: No, by Allah, I will not give you more than four hundred dinars - he either said: in instalments, or he said: at fixed times. Abu Rafi' (may Allah be pleased with him) said: By Allah, I could sell it for five hundred dinars in cash, and had I not heard the Messenger of Allah (peace and blessings be upon him) saying: "The neighbour has more right to his adjoining property," I would not have sold it to you. (These are the words of al-Humaydi.)
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 973