Yes. Students can buy and sell books at no cost.
No. You can search and buy textbooks from other students without having an account. Only when you want to post your own textbooks will you need to create an account.
Yes. You can have one primary school (the school you are currently attending) as well as two secondary schools. Although a textbook can only be posted to one school, having multiple schools allows you to manage postings at each institute.
Yes. Login to the Books2go website and then edit your account. A link is available to delete your account. Your textbooks will also be deleted as part of this process.