I’m not convinced a larger contingency alone solves this. AED 429,600 is already about AED 5,054 per m², but that figure says little without a scope breakdown. A vague lump sum plus 20% can still fail quickly.
Request separate prices for demolition, electrical, plumbing, waterproofing, finishes...
I’d put a value on reliability before deciding. The gap is AED 3,970 a year, but asking rent is not necessarily achieved rent. Estimate vacancy, preparation and reletting costs, then compare that total with a smaller increase for the current tenant. Confirm the required notice and permitted...