When it comes to something like paintball/airsoft a special type of insurance is required, the package policy that you would purchase has varying levels of liability coverage. These package policy's are not cheap think thousand's of dollars, and I mean multiple thousands to start since you would be an entry level customer and the insurance company would see you as high risk, hence why that would charge you more. That's even if you can get a policy, the way it works is if you are indeed interested acquiring insurance for such a thing then you will need to approach a local insurance brokerage and address them with your request, in return they will provide you with the appropriate information and contacts for the small handful of agencies in Canada that cover such things. Once you have contact the agency you will be required to apply for coverage, its not a simple pay and get it kind of thing. You better be prepared to be provide detailed information on your business and nature of the events that you will be covering, the screening processes is extremely difficult and can take a fair amount of time. Be prepared for the possibility of being denied. If you are approved then that is when you can begin examining the amount of coverage you wish.
That is the short version, the detailed version would take me a an hour to explain.
"Its only a little bit on fire"