Could the fact that he said "Dubai residents' possibly mean that he is talking about what in England is called 'Rates' and in other parts of the world has a different name but is an annual tax on the value of the property? It would be payable by the owner but probably passed on as a rent increase to tenants.
When Saudi mentioned income tax many years ago so many expats said they were leaving the idea was scrapped, particularly the US citizens who were already paying USA tax on a portion of their salary.
Just a thought.