First step to evaluation: Type your words in quotes into google. If you get less than 40k results, you generally have a brandable.
Dubai is not commonly referred to as DubaiCity, therefore you have added an extraneous word, making a two-word phrase into a 3 word phrase.
On the other hand, NewYorkCityVacation is worth mid $xx,xxx because the name of the city in New York is New York City. Search engine results are in the billions. You results were less than 100 for all 5 domains combined.
Brandables can be sold to end users for reg fee or a small profit.