This is referred to as a solitary area split a/c system and will generally cost from around ₤ 300 for the materials only to around ₤ 1200 completely installed. https://www.massschneiderwerkstatt.de/firmeneintrag-loeschen?nid=14239&element=http%3a%2f%2fxn--e1adphegqz7e.xn--p1ai%2Fuser%2Fpantsgarlic73%2F