Wendy, absolutely no money! My personal opinion. I buy something like a large box of 'Celebrations', and give each kid that comes to the door (as long as they are dressed up) a handful. Seems to work around here. I have the same about a dozen kids coming every year. They started when they were little toddlers, with their mums hovering in the background, and some are now scary looking teenagers. I normally get a bit into the spirit and pop on a witch's hat when there is a knock on the door, paint my nails purple and wear black, with some very large spiders stitched to an old top. I also pop up a broom just inside my porch with a sign on it: "The Witch Is In!"
A few years ago I scared the life out of an elderly gentleman who lived just down the road and didn't know me. His grandson had been playing football in his garden, and the ball flew into my garden. Granddad came to retrieve it and was greeted by me, all dressed up!