This was brought up way back when I was chair of automotive, along with other pieces of equipment. Once you’ve been around the Makerspace a while, one (not just you) finds that there are too many folks that abuse the tools and equipment and just don’t give a shite.
A good almost idiot proof recovery machine is about $5000. Plus maintenance and whatever goes missing / lost / broken / reclamation… Couple this with the new “freon” and the now “old R134” I don’t see where this is a “necessary” tool.
The simple fact of “servicing a mobile ac system” is that when the system has a system failure, it is usually something catastrophic in the system, and there is no refrigerant to recover. A "recovery system would be “nice” for adding the proper amount of freon by weight, but not at the cost of $5k.