I wouldn't plan an overnight unless you have spent at least 1 short time session with her. How is your Spanish speaking, I would say close to 99% of the girls don't speak English so unless you are comfortable doing all talking through a translator I wouldn't bother. Rates are very reasonable but you are a Gringo they will try to get as much out of you as they can, if you don't speak Spanish you will have a hard time negotiating. As a girl in Thailand told me, I am rich, I said no I am not she told me I could travel half way around the world for a holiday so ya I am rich.