Prices vary too widely by property and system to treat one headline figure as reliable. A useful quote should describe the proposed system and what the installation includes.
Main cost factors
- Number and size of indoor units.
- Single-split or multi-split configuration.
- Length and complexity of refrigerant pipe runs.
- Outdoor-unit location, brackets and safe access.
- Electrical supply and any new circuit requirements.
- Condensate drainage.
- Scaffolding, lifting equipment or difficult access.
- Finishing, trunking and making good.
- Manufacturer warranty and ongoing servicing.
Compare like with like
Ask each company to identify the unit model, rated capacity, sound data, warranty, included pipe length, electrical work, commissioning, VAT and any likely extras.
Be cautious with remote-only estimates
Photos and measurements can support an initial estimate, but unusual pipe routes, neighbour impact and electrical constraints may only become clear during a site survey.
The lowest quote is not automatically the lowest total cost. Incorrect sizing, poor condensate drainage or inaccessible equipment can create avoidable costs later.