I've put triangular 1.5" thick studio foam on walls, doors, windows, used .5" thick x3 yoga matts plus one entry way rug on the same window the exercise matts are stapled to. All worked well for not hearing my neighbors and them not hearing me as much, or as bad as it could've been.
Bass traps depends on frequency and only for audiophile standing wave reduction.
However, the bass traps will redice annoying reflections but not rid adjacent rooms of slamming bass. To reduce the bass to a minimal less annoying spl for adjacent rooms the best way and cheapest way is diy @ 1 person labor = 3 months depending on budget. Less time if budget is swell

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2x4 channel transmission reducers for whichever walls you have issues with. Replace insulation with denim r13 - r19 o ( 14" x 4ft rolls ) for two walls of the ultratouch insulation recently @500 $ home depot. My walls are 12' wide 9'ft height x2 = 500 $ total. Sheetrock I used 1/2" but should've done 3/4" . The best way prior to installing the denim insulation is expensive but most effective. Use the thickest and cheapest bulk rolls of vinyl. Do research on thickness and frequency reduction. It definitely doesn't have to be 1/4" thick, but that's about my thickest if it were me. Staple your vinyl to interior of walls prior to insulation batts, install insulation to vinyl with spray glue, put another "wall" of vinyl to encapsulate your denim insulation using staples, then install your 3/4" sheetrock wall joists. If you can afford it , instead of sheetrock use hardy board or similar cement walling. Paint, cover wall with carpets, and doors need to be sealed by every way possible use foam spray between every vault of air when you expose your walls. Thats 4 months work for little ol' me. Cement floor good for you, wood floors? Styrofoam then carpeting x 2 layers cheap 1 color best highest quality on top.
Just found a cheaper way for quick fix. Keep existing drwall on. Go to home depot special order quiet rock at 5/8" for your room and opposite rooms ( that's a new sheet rock wall for all your issue walls including your room .) Put them on, tape, finish. Easier said than done.