With the price of many things going up, it is getting more difficult for many people to buy things they usually do. It may be possible to make your own halloween costumes.
One source for ideas is Pinterest. It is an online pinboard. If you find sites you like online you can "pin" the website to your boards and share with friends.
I have made a board with some costume ideas and other halloween ideas. There are also boards with other holiday ideas.
Other resources for halloween costumes are the thrift stores. Savers in Fargo has brand new halloween costumes that may be less expensive than other stores and they also have a selection of used items to make you own costumes. Other thrift stores have halloween decorating items, both new items and used.
Now is also the time to keep an eye out in stores for sales on candy to hand out.