How much is Ethereum name service fee?

Could you please elaborate on the pricing structure for the Ethereum Name Service fee? I'm particularly interested in understanding what factors determine the cost and if there are any variable fees associated with the service. Additionally, I'd like to know if there are any discounts or promotions available for frequent users or if there are any hidden costs that I should be aware of. Clarifying these points will help me make an informed decision about whether to use the Ethereum Name Service.