You are about to spend money you did not plan to spend, in the middle of the night, on something you cannot postpone. The least a clinic can do is tell you the figure before you get in the car.
The prices
Everything is priced after the examination and the X-ray and before any treatment is started. You are told the number, and what it is for, while you are still able to say no.
Why the last line is a range
Because a nerve dressing and a full root canal are not the same job, and neither is a rebuild and an extraction. The examination and the X-ray exist to find out which one you actually need. Until that is known, any single figure would be a guess, and a guess printed on a website is how people end up paying for work they did not need.
Where your case sits in the range is explained to you before anything begins, in plain language, with the X-ray on the screen in front of you.
What the range covers
The AED 1,500 to 2,500 is the whole emergency visit: the clinic opened for you out of hours, the examination, the X-ray, the anaesthetic, and the treatment that gets you out of pain that night. It is not a deposit and it is not a first instalment.
Work that should properly be done later, a permanent crown over a treated tooth for instance, is planned as a separate appointment at normal prices. It is not bundled into the emergency and it is not sold to you at three in the morning.
The phone call is free
Dr. Sarhan answers the phone himself. Describing what you are feeling costs nothing, and a fair number of calls end with him telling you it can safely wait until morning. That is a normal outcome of the call, not a failed sale.
You can also send a photograph on WhatsApp and get an honest answer about whether it needs tonight.
Insurance
The clinic works on a reimbursement basis. You pay at the visit and claim it back from your insurer afterwards. A full itemised invoice is provided every time, which is what the claim needs.
Whether your policy covers emergency dental treatment, and how much of it, depends entirely on the policy. Nobody at the clinic can tell you that, and anyone who says they can is guessing. Check with your insurer, ideally before you need to.