RedGreen/JomiMike -- A few years ago, a couple I knew put together a business plan to do just such a thing. It was based on the autohobby shop idea that you might find on just about any larger military installation. Lots of bays you can rent by the hour, day, week or month and a community tool room.
It all went really well until they went to see the insurance agent. The liability issue shut them down -- they just couldn't get insurance. Just think of the hazards and all the cuts, bruises and other injuries we sustain working in our shops. With a community shop idea, you have no control over what these people do and you're giving them access to tools that can maim and kill. You can come up with all kinds of nasty scenarios. So can the insurance dudes.
Not saying it can't be done, but you aren't the first to come up with the idea. Who knows, maybe you can be the first ones to get passed the insurance roadblock.
Your reality check for the day
John