‌The cost of installing an air conditioning unit or system does vary considerably. Factors to consider to work out the complete cost include.The size of the area you need to cool or heat.The efficiency rating of the unit you might be quoted forKilowatts of heating/cooling needed to regulate temperature Location height/ difficulty or bespoke fitting involved in installing. Distance between the indoor and outdoor units. Materials needed and engineer hours involved to complete installation.Type of unit. Units to consider are wallmounted, floor standing, ducted, and cassette.