An NRI is legally allowed to rent out the property he owns in India. The rent income can be received in two ways:
1. The rental income can be deposited to the NRE or NRO account with an Indian bank. Rent proceeds received in these accounts can be freely repatriated.
2. If one does not have an NRE or NRO account, the proceeds can also be directly remitted abroad but one would need an appropriate certificate from a chartered accountant certifying that all taxes on the rental income have been duly paid.