Too bad at least for me the main issue is getting cool temperature at night while sleeping. I don't care as much if it is 30+ C in daytime.

Here in southern Finland weather is cooling down, today it was a nice +25C or so, and what is more important, it seems nights are becoming cooler too (under 20 C). As I've mentioned before, the main issue here seems to be that the apartments are designed to keep the warmth inside, not so much to stay cool in warmer weather.

Like for instance yesterday night, I measeured that outside it went down to +19 C or so... but for some damn reason the indoors temperature just stayed at around +30 C or so. I need cooler to a good night sleep! I opened the small airing windows to get a draft, but managed to get the temp down to only +28 C. What the heck?!?

And no, heating is not on, other than what warmth dissipates from the TV, my laptop, refrigerator and body heat.

Yeah, I need to buy a good air conditioner too, installed. I just first need to get a permission from the housing community (ie. the owners of all the other apartments), mainly if someone is afraid they will be too noisy. In Finland they don't even sell these kind of cheaper "window A/C units" as I think they have in the America:

https://www.ebay.com/itm/8000-BTU-Window-AC-Unit-w-3500-BTU-Heater-115V-Home-Air-Conditioner-w-Remote/253797807070?hash=item3b178733de%3Ag%3Aug4AAOSw51JbZnef&_sacat=0&_nkw=windows+air+conditioner&_from=R40&rt=nc&_trksid=m570.l1313&LH_TitleDesc=0

Here you can buy only either portable A/C machines, or split units. Maybe it is because here there are generally quite strict rules what you can install outside your home (how it affects how the apartment house looks outside (the outside units can only be installed on balconies due to that in apartment houses), the noise it will make to neighbors etc.

I already have a cheapo portable air conditioning unit, but it is VERY NOISY (like a vacuum cleaner, lower noise though), and not too efficient, ie. good if I can get the temperature down by one or two degrees... but at least it takes some humidity out of the air too. It is better than nothing, or a mere fan.

Then again, here you never know what you will get. Last summer, for instance, was quite cold. We were happy if we got over -20 C day temperatures, and e.g. in Helsinki the temperature never went to +25 or over, during the whole summer (compared to this summer where it felt we got +30-32 C for several weeks, on and on and on...). So who knows, maybe next summer will be another cool summer. I liked this summer better.