try to find a broker in the area that specializes in commerical lines. it's a specific type of ins that you need, but they should be able to point you in the right direction. And I would absolutely get Ins. Waivers or no waivers.. You don't want to get held personally responsible. You can always call your agent if you have one for homeowners ins and such. They can point you in the right direction. It's always when you DONT have it that you need it!!
Personally I wouldn't take the risk. But of course I'm maybe a bit on the paranoid side! ha ha