GGB Less than a dine-in restaurant of the same output, because there is no front-of-house to fit out and the footprint is smaller — but there is no honest single figure. Price it line by line: the trade licence (DET or a free-zone authority, published as a calculator), the Dubai Municipality layout assessment and food permit, the Ejari registration if you lease a unit, the kitchen space itself (a shared facility fee or your own rent), fit-out and equipment, the food-safety system, packaging and the first months of salaries. Then test the per-order margin after aggregator commission before you sign anything — that, not the capex, decides whether it works.
From Cloud Kitchen Setup in Dubai: Costs, Licensing and the Real Economics — the full reading, with the method behind this answer.