One of my friend has provided me services of a contractor for construction of my house on friendship basis. There was no formal agreement and mutual understanding was that he was doing it without cost. After about 2 years of the construction of house, he has now demanded a fee for his work. He has never demanded it before ,however, after a dispute with him in another matter he has demanded the fee for his work. Is it lawful for him to demand a fee for which it was understanding that it is free

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

If this person has clearly stated to you that he does not want any payment for his work and that he is offering it voluntarily, then he has no right to claim anything from you. However, we advise you to give him something as a kind gesture and appreciation.

The Prophet, sallallaahu 'alayhi wa sallam, encouraged rewarding those who do good to us, as he said: “Whoever does good to you, reward them for their goodness.” [Abu Dawood and others.]

Allah knows best.