Ninja Katze
I am lucky since mine and the surrounding communities always put on town events and everyone is trick or treating in the town centers. They always put them on around dinner time so we seem to be there by ourselves. We always want to dress up, but never have the money for costumes.
That is very cool, I'm not that in tune with my community. I might paint my brother's face or something before he goes trick or treating. I got to do the Dark Night Joker last year.
As I said, every day should be Halloween, so a good portion of my wardrobe can pass as a Halloween costume. With a little creativity you can make anything into a costume. I used a black cat suit (like a jumpsuit I already had, not a costume) and a kitty mask I painted gold to be the Egyptian Goddess Sekhmet. She is like a destruction deity and has the face of a lion.
If you don't have any inspiration I can recommend searching around for some DIY costumes on google.
DIY is more fun than buying anyway, and much cheaper. But you get more pride out of telling people you made it yourself.