By SJ Mohamed: both books, for one price.
R199, once.
You get a book key straight after paying. The book is read in Scriptorium, which reads it for free on Windows, macOS, Linux and Android. The key opens it on 2 devices, a computer and a telephone, say. It cannot be printed or copied.
Paystack takes the payment and sends your receipt to that address. It is kept with your purchase, so that you can be helped later, and for nothing else.