My brother is going to a psychologist and one of my best friends is psychologist to, i pass you what i know about the profecion in here, the psychologist of my brother is fully scheduled almost all the time but he have a good client portfolio and long experience in the field, the hour rate for him is 300 pesos per hour that make 60 usd oficial rate (if you use family help to save the dollars back home limited to 1500 usd per person in your case 3000 between you and your wife per month at oficial rate "you need to have all legal to use this" i always use this way as it save me lot of money and allow me to save dollars outside) if you don't comply the requeriment for this one you can use the black market that will give you 43 usd per hour, or just stay with the pesos and spend them. In any case how much you get per hour depend a lot on you, your type of clients, and your hability to speak perfect spanish that make a big diference in your area if you are going to have local clients, so take that numbers as just a case there is a lot of diference i supose between psychologist and i have no idea in your case that you are attending only expats.