The Comunidad de Madrid has not declared zonas tensionadas, so the national rent caps that bind in Catalonia do not apply here. That is a political position rather than a permanent feature of the law — it can change.
Beyond the fianza a landlord may ask for a limited additional guarantee, commonly up to two further months. Demands well beyond that are not standard practice dressed up as market conditions.
Comunidad charges are normally the owner's and IBI always is. Check which of the two the advertised rent is quietly assuming.