The quoted prices I saw for installation were a lot higher, more like 700 euro, but that probably depends on the cost of labour where you are.

There are also non-monetary aspects to this issue - I'm not allowed to make any modifications to my facade on account of it being made out of asbestos, for example. I'd have to get a specialist to cut the hole to make that work. It's also a bit tricky to fit in an outside unit - or inside unit for that matter - on my walls.

I'm in complete agreement that mini splits are superior, but the downsides do exist and need to be acknowledged.