Cómo preguntar el precio

If you want to know the price of something, ask Qué precio tiene(n):

¿Qué precio tiene una doble? What price does the double room have?
¿Qué precio tienen estos zapatos?What price do these shoes have?

To ask the same more informal, use cuánto cuesta(n):

¿Cuánto cuesta una doble?
¿Cuánto cuestan estos zapatos?
In restaurants and hotels prices are frequently announced without VAT (sin IVA), so we recommend you to ask:
¿Con IVA o sin IVA? – With VAT o without VAT?
If you want to know whether you can pay cash o credit card, ask:
¿Puedo pagar con tarjeta? – Can I pay with a credit card?
¿Puedo pagar en efectivo?
– Can I pay cash?
If you are looking for something cheap, say:
Me parece un poco caro – It seems a little bit expensive
Estamos buscando algo económico – We are looking for something cheap
But if the price seems too expensive, you can say:
Me parece muy caro – It´s very expensive
¡Es carísimo!
– It´s too expensive!

Please, never say money no problem! Spanish don´t like people who say things like that.