It costs 60.00 per year (you want a premium membership). The lower membership does not give you the same return in profits....but yes, 60.00 a year and they supply the website...and they are good about product ownership and copyright laws. They have options for, and regular sale dates....You get paid your earnings by PayPal. They supply a tax form, and all kinds of data like wishlisted items, number of sales per product, etc.
As a home business, a small business's expenses are tax deductable if you want to itemize. Anything you buy for your business is tax deductible, including space in your house (one room for an office). Once you start, set your prices at 3.00 and above for products to cover added costs for anything under 3.00 (more is taken out of profits from PayPal). All your paper, paper clips, computers, and apps you use are tax deductible. However, when I started, I didn't deduct the first year. I can't say enough about making and trying to stick to a business plan, and I will say my TpT first grew because it was positive, my phone went chiching when I sold something, and it was great to get good feedback. Google offers something similar to TpT, but their cut for the author/designer is much higher. TpT (Teachers Pay Teachers) is the number one teacher materials business in the world and virtual products are gaining lots of momentum, as well as items which support social justice. My best advice is that you make what you are good at......and only what you feel good at......and find your niche in creating different products. Starting your own business is very time consuming, exciting, and requires an internal commitment for success.....and a plan. Hope this helps!