Not good idea to go BIFL. Newer models are way quieter and more energy efficient. Better to go cheap and change each 4-6 years. Some companies in EU offer 5 y. warranty.

One unit of high class Daikin cost around 2X middle class or 3x cheap ACs. I got 4x Daikin on my mountain house. The first one is bought 2008 and still work flawlessly. One of the 3 newer ones bought 2017 died last year. The compressor change costed like 1 cheap AC.

For my apartment in the city I bought middle class toshiba with 5 y. warranty this summer because the central heating runs on russian gas. I don't expect to last more then 6-7 years. Having single units is a way more energy efficient compared with 1 big AC unit, unless you combine it with water to water heat pump. In this case check the LG models.