Cheap lifts to make better use of the upstairs in smaller shops and restaurants. Parent and push chair size. (3 or 4 people)
How often do you look up at the upper floors of high street shops and see blank, or even blanked, windows. Space wasted. Or stairs no one would climb.
One story lifts. (One each floor?) Small prefabricated extendable cages with a single hydraulic ram to lift and lower. All the safety devices built in. Factory made in advance, just to be fitted on site.
This is the cheap answer for elderly people living in housing with stairs also.
A whole industry waiting to go. Factory made == a fraction of the cost. Of course shops will soon be a thing of the past?