How much of the local language do you need for daily living? Are local language classes/tutors available and affordable?
You need to learn Spanish. Most people here do not speak English. You can get a tutor for about $40 mil pesos per session. - Aug 2019
The more the better, but because this is such a tourist town you can get around decently at first with just "resort Spanish". Most people are pleased when you try to speak Spanish and will help you learn. - Mar 2012