Sorry to spoil the party, but you will have some BIG challenges...
1. It is very difficult to ensure people clean up after themselves. Despite encouragement, threats, warnings, you will always get people who leave a mess.
2. How do you ensure someone does not stuff up your 3D printer or whatever? Loaned equipment is often abused.
3. Scope probes. They will be broken, run over with chair castors, pulled on or used a skipping ropes. And the coloured ID rings, probe hooks and ground clips will go missing on a regular basis.
4. O H & S. Someone gets injured by cutting off their thumb in the metal shop and you get sued.
5. Drill bits. The 1/8" and 1/32" bits will be broken and go missing. Always. So you sell drill bits from the vending machine. Great way to make money. A cheese people off.
6. 1K, 10K and 100K pin-though-hole resistors will be scarce. Even if you have a vending machine.
7. Someone loads cryptolocker malware on your public PC at 2 in the morning and needs YOU to come in and fix it.
8. Someone connects mains to one of your logic analyser inputs and blows the crap out of it. Why? Because they can.