Depending on how you choose to homeschool, it can be very inexpensive, just a few hundred dollars a year, or it can cost thousands for premium memberships, tutoring or outside classes and activities, larger homeschool co-op fees, supplies and high-priced curricula.
Our umbrella group tries to keep costs low by sharing available classes and resources that any of us are participating in or that we think are good possibilities for others, and also by encouraging our members to contribute to our learning and social community from their areas of talents, interests and expertise. It is possible to get started with a full homeschool plan for less than $100, but it does require some planning and effort. See https://cathyduffyreviews.com/homeschool-reviews-core-curricula/unit-studies-all-in-one-programs/all-in-one-programs# for all-in-one programs. Online, Easy Peasy: All inOne Homeschool and Kahn Academy are Free Educational Sites