Home Exercise

My name is Simon and I care for my father who had a stroke 6yrs ago. Recovery has been very slow where his walking has improved since the stroke, but has detoriated over the years. We've tried various therapys such as float tank therapy and FES, FES unfortunately didn't work for my father as we found the device to only work intermittently, and tank therapy was difficult logistically. The problem we have now is CV-19 so the logical thing now would be to home excercise. One of the best forms of excercise would be to use an Anti gravitity treadmill which are expensive to buy, but would love to hear from anyone that has bought one or even rents one. Any information would be greatly appreciated.