I get my drinking water from "Al Safa".
The bottle replacement usually costs about 8QR to 10QR.
But if you buy 50 coupons from Al Safa, the price becomes 6QR per bottle with free delivery.
Their water is great and their delivery schedules are good also.

I don't have their phone number just now, but here is the phone of the driver that delivers to my area (Markhia):

Shafi'u Rahman: 5706011