Came across this Exxentric belt squat, which is used by some college and pro teams, including the Baltimore Orioles and the University of Minnesota.
With a small footprint, it looks like it would be perfect for the garage gym, but is pricey at around $3100. One bonus is that it can also be used for rowing, triceps push downs, even lat pulls with a pulley attached to a chin up bar or rack crossbeam.
Does anybody have experience with this flywheel technology? It is relatively new in the US, but I imagine the price could come down with more units being sold.
Part of the high cost is the associated software packages that can measure force, similar to a Tendo machine. If it could be purchased without this, the price should come down considerably.