Visiting Bogota in early February 2015 (Bogotá)

I am from UK. I am planning to visit Bogota in Feb'15 with the intention of teaching English and learning Spanish. I have few job offers (only promise- not guaranteed) from English teaching agency and language centre. Is this practice is normal or once I am in Bogota, I will have to find a job my own.

Also I was told that as British citizen, I am allowed to enter Colombia with a free tourist entry visa for 90 days stay and once you are happy with your work and other facilities you can apply for a work permit..... or you can leave with in the tourist visa period. I hope this is true and I am not breaking the country's rule.

What kind of rent I can expect for a single person accommodation in a safe area convenient for travel and other facilities ..... sharing a room in an apartment or private single apartment. ( I was told it could be with in US$ Protected content month.)

Warm welcome to all your precious advise..... Thank you

Ash