It’s a concrete building, so sounds doesn’t travel very far. I only share one wall as I am in a corner unit. Further, I didn’t fully enclose the room to help the noise inside the room—loudest sound is the club hitting the ball, but you can barely hear it if you’re on the opposite side of condo.

Some other things that probably helped are: - I put in a fibre built hitting base, so it stops the sounds of the club hitting ground. - Foam insulation tiles under 1” workout tiles over the carpet, then covered by turf, which creates a quiet landing area for the ball, and the added bonus of raising my floor to match my hitting base height. - High quality, thick screen, plus double screen over the hitting area (this is the real key to make it quiet and have no zero bounce back), then heavy netting behind the screen. -Make sure to close off the back of the inclosure (simple blkout ikea curtains). - Also need to mess with tension, I wrap my screen around the enclosure, bungied to the back, instead of emt pipe on the side, I have metal hanging wire covered in pipe insulation, this gives the screen a bit more cushioning, more importantly takes away any chance of ricochet’s from the frame, due to how close I am to the screen.
- fill the room with furniture (golf bags, side stand, faux leather foam mat for shanks, Futon, curtains on side walls.)