[dredmorbius]

Keep in mind that we're talking, in general here about typical commercial retail: storefronts, restaurant space, small markets, possibly office or light industrial space. Not highly-specialised large-scale hospitality, scientific labs, heavy industry, etc. Yes, those exist, yes, there are vacancies, but *the typical case is going to be pretty quotidian. Don't let the perfect be the enemy of the sufficient.

For what it's worth, one of the specialised use-cases probably more likely to be encountered is large-volume food retail, a/k/a supermarkets or grocers. These have distinctive footprints, refrigeration, stocking capabilities, and the like. A few years ago the failure of a large regional grocery brand in the US resulted in numerous commercial vacancies of precisely this nature. There was some controversy when the successor to the chain held on to many of those parcels for years. There were still numerous vacancies at three years after final closing, several locations were demolished entirely, and the last property wasn't repurposed until six years after the original chain had failed. This despite pressure and desire to provide grocery services in the area. As the successor company was also a grocery chain (with operations in the area), stalling transfer of the properties was effectively a way of hamstringing their competition. The space wasn't easily converted to other uses (this happens, Sports Basement at the former Presidio PX in San Francisco is an example, a former A&P supermarket in NYC converted to a community center another), and food retailers hoping to expand had few other options. Notably, despite exploding vacancies in non-food retail, former strip-malls and shopping centres can't easily convert other retail space to groceries.