Where in Tennerife should I move to?

Don't want to put a downer on it for you but unemployment is high here at the moment, 28% of the population are unemployed so finding a job is going to be very very difficult. £800 would last you about a month. Any apartment you go for will cost you one months rent and one months deposit, the average rent is about 450€ a month so that's your £800 gone before you start. That would be for an apartment out of town too so then you have to pay for transport to get to Los Cristianos or Playa de las Americas. The only work that is available seems to be telesales and is commission based and not many people like cold callers. If I were you I'd think carefully about your move, the gr isn't always greener.