Do you have requirements for the WiFi Standard?

Do you want to build up a new system or adding to your current setup?

For the price point you could look into the AVM Fritz Ecosystem. Their Mesh solution is quite hassle free and for 200€ you could get WiFi 5 capable devices on the used market.

Not sure how well they work with other brands, so you might want to invest in a FritzBox and FritzRepeater (should be in the budget used).

Anything above WiFi 5 could be out of your price range, especially new.

Ubiquity APs with WiFi 5 could be in your budget, even new. Look into the AP HD. You will need a controller installation though, weither on your desktop or on a NAS, Server. You do NOT need to buy an appliance from them for management. They do not make it clear on their website.

The infuriating thing is Yves Guillemont does not pay the price, the people in that studio paid the price. Yves probably still shitting money and banking a big bonus.