60% of all tickets sales is going to the prize
and 30% for the operation cost, signature campaigns , affiliates , servers , ads etc
I like your idea of donating some of the money to a charity. We are living in very difficult times right now and if we have spare money for gambling it should be okay to give some of that money away. Taking 10% out of the winnings shouldn't be a big deal, we will happy enough to actually win and make a profit no matter what. Also 10% can lead to a decent amount when the raffle becomes big with many participants. What I don't like is that you want to use 30% for operating costs and advertising. That seems way too much in my opinion. Are there really so many costs involved in running a small raffle? I would rather have less advertising and pay more money back to the gamblers. There are already a lot of raffles out there and the best way to distinguish from the would be to have the lowest house edge or the best winning chances. Maybe start smaller to first get some customers and once there is enough demand you could still increase the whole operation.