Adjustable Weight Bench for Home Gym, Foldable Incline Decline Sit-Up Bench Workout Equipment for Full Body Strength Training, 795LBS Capacity for Chest, Shoulders, Arms.
Currently $62.28+tax at Amazon but they sent me two, refunded me for the second one, and let me keep it. So cut out their infrastructure while saving ~$8.
I'm impressed with it so far. It has two spines for the back for extra support. Both the seat and back slide to discrete positions (9 and 4 positions, respectively). The bench goes from 90° straight up to down to -25°. It has thickened, rounded-rectangle alloy steel construction: not the old school tubular frame design that made your benches wobble. It has a 795lbs capacity. It's probably the best bench I've seen under $100. The heavier weight capacity means it dampens vibrations and mitigates any risks for tipping: extremely stable.
Must pick up from downtown Berkeley. The box weighs 29.7 lbs so it's technically possible to transport on a non-rush hour bus/BART.