centrifugal fans are very quiet. it's there biggest benefit.
you can also hand the fan by bungees which will absorb the vibrations

I find using plastic ducts absorb a lot of sound. I sleep in the same room as my grow so
I would know. The aluminum ones make the most noise.

You can also considering blasting metallic when ever the fan is on.
Your neighbors will be so distracted by that, they wont care about fan noises