If you're thinking of buying an air-conditioning unit, consider these points:

• SIZE: physical size and weight. Also consider noise (internal and outside units)
• POWER: either BTU/hr (British Thermal Units)or kW (kiloWatts)
• FEATURES: CFC-free refrigerant, thermostatic control, condense evaporator, dehumidifier mode, timer
• CLEANING: ease of filter removal
• MOUNTING: floor standing, wall mount, window, ceiling mount, roof mount, portable unit