I know this is more hardware related, so please let me know if I should move this post elsewhere.
I built my first server earlier this year, and put buying a UPS on the back burner. Unfortunately for me, this might have already been my biggest mistake since going down this rabbit hole. The rental I’ll be in for at least another 10 months has some questionable wiring (a lot of rooms/outlets wired to the same breaker), which I believe has created some electrical anomalies and possibly killed some of my computer components. The memory on my PC went first, and now the 7-month-old PSU on my server is toast.
Bear in mind, I am not an electrician, so I could be entirely wrong on why this has happened. Regardless, it's time I invest in a UPS. I have searched forums, blogs, YouTube, and cannot find consistent pros and cons for any of the big manufacturers. It seems like APC and CyberPower are the two big consumer grade manufacturers, which is probably what I should be looking at.
It doesn't sound like you need a UPS. It sounds like you needed automatic voltage regulator.
It'll condition the power so it's clean, and if it's not clean it'll cut the power off.
Many good UPS's have a voltage regulator built in, but then you have the hassle the battery and everything. Up to you depends on what's easier to find for you locally
So I'll just speak very generally, and assume you mean power conditioner, because generally a PCU does the VRU stuff, but not always the reverse.
So let's say you plug a VRU into a faulty socket: the regulator will only power up the passthrough port when it has the input source stabilized to meet whatever it's conditions are, and then it provides power - cool. What happens when that faulty wiring starts flipping on and off super fast, or has a drain for more than 5 seconds that doesn't meet the line input conditions? Dead output.
Now let's say we plug in a UPS which has all of the above features, but the wiring goes to fault - UPS beeps and provides power from the battery. No loss in power, and the server isn't going down and rebooting many times throughout the day.
Anecdotally (meaning I've seen this hundreds of times live, but never seen a study), a UPS can take a LOT more punishment from power SURGES like lightning strikes, which I would be concerned about if the wiring is also faulty. There may be no proper grounding or surge protection in the building he's describing if the power is this bad.
I've not heard of any "gas venting" for these small batteries, but maybe I'm not up to speed on that.
As far as active cooling fans, that would only be while on battery, not a constant thing. In the case of just preventing line faults from flipping the current on and off, only a battery will prevent that and stop damage to a PSU.