If you open an airsoft field in Montreal, I will come VERY often !
Seriously, I have been to Action 500 (formerly action commando) and it smells really bad, it's like a mix of old paint+dust that makes the air really irritating and bad. If you could keep your place clean, it would be great.
As people said, Rentals ! It will help you bring new people, BBs, maybe a gundoc that comes once in a while, some basic parts/tools, decent food, water (not a cheap fountain, get something with cold water with those taps to fill out your water bottles quickly) and somewhere reachable by Bus or Metro (important, I don't have a car).
So, try to keep it clean and I hope to see a new field here !