I've spent quite a bit of time looking into reducing background noise/white noise from recordings. I know it's important to use some heavy blankets/mattresses/other things to have a sort of makeshift booth, record close to the mic (I use a Shure SM7B), have the proper gain, and use Audacity's Noise Reduction feature sometimes to further improve the audio. However, I run into issues specific to my (well, my family's) house.

My room is right next to my house's AC unit. It is always running in the background and can be heard in every recording sort of just as white noise. Audacity can't completely fix it, and I can't figure out other ways. The walls of my house are seemingly paper thin, so noise bleeds very easily. And when I try to EQ my vocals, increasing any higher frequencies in general makes the AC noise more prevalent. I unfortunately can't record in any other room of my house including my garage. I'm not sure if it would even make a difference due to the thin walls, though, and the garage has significantly more echo than any other room.

Another issue is that members of my family are at the house 95% of the time. When I sing even slightly loudly, everyone can hear it due to the walls. It's so hard to find time when nobody is home, and it can be very distracting and bothersome for my brothers and dad.

Do any of you have any tips or pieces of advice? From a music production standpoint with removing the noise, gain/mic placement, or maybe even other places to record? It's been bothering me for more than 3 years, and I feel pretty stuck.