Yup! Even units with one exhaust need 2 fans. Many standalone models even have a small 3rd fan near the condensate reservoir to re-introduce moisture, collected when chilling air, back into the exhaust so they don’t have to be drained as much.
The nice thing about inverter units is they only run the pump and fans as hard as it needs to obtain its objective. Once there, it can spin down and get much quieter. I used to have floor units and hated sleeping with those. All through the night you would get fan noise and a huge CLUNK as the compressor kicks on or off. We upgraded this year and the ramp-up is so much easier to sleep through. There is still fan noise, but much quieter and becomes white noise after a while.
I use kimai. It’s gotten much more stable over the past couple years and there is a mobile app. (I think it’s a couple bucks now, but works pretty well)
It runs in docker so it’s pretty easy to set up.
I have one customer who is pretty nuts about bills and this is the only way to track and invoice all that nonsense.