sergio said:"Like the others said..."
If you are going to teach English to Spanish speakers please do not make grammatical mistakes.....AS I SAID!
Haha, excuse me? I don´t see any grammatical mistakes in what I wrote. I really was referring to what others had said previously.
And also, EXCUSE me? Even if I had made a mistake, do English teachers have to be perfect now? We spend all day 5 days a week talking to non-native speakers, and almost never talk to a native speaker, and you expect us to never pick up any Spanglishisms? Well I´ll excuse that haughty remark on the assumption that you´ve never taught English, because I have had a number of English-teacher friends here, and they all confess that it happens to them. And as a linguist, I can assure you that it is also a completely natural process. This is also, in part, why many institutes prefer English speakers who do not know Spanish - they are less prone to these mutations.
Holas, to answer your question, I think a flatshare would be your best bet on an English teacher´s salary. You would not be able to afford your own apartment here, especially if it is a temporary rental, furnished, etc, if your only income are English classes. If you´re willing to share a place with others, I recommend: www.compartodepto.com It´s like Easyroommate, but for here
There is generally a lot of job-changing here. You will probably work for more than one institute, as it isn´t too common that one institute alone will give you a full work load (20-30 hours a week). If you´re happy with your classes/institutes, your classes should last until December, unless they are test prep classes, in which case your classes could be as short as 2 or 3 months long. It really varies.