Spanish schools in Madrid?

I'm moving to Madrid in October. I will be working for a logistics company. I still have some basic Spanish language knowledge but I need to improve it for sure. I'm planning to travel to Spain already in August to to take a crash course for some weeks. I'm thinking of booking with Ailola Madrid (http://www.ailolamadrid.com) which offers very good prices. Anyone can recommend it?

Also I would like to know how much rent I need to pay for a small apartment (if possible more or less central)? I only need one room or something like a studio. Is it difficult to find something and where can I find the best offers? AirBnB is great, too, but rather expensive if you plan to stay for a long period.