Buying and selling are two sides of the same coin: to understand one, you need to understand the other. This flip book works the same way. Read this side first, then flip the book upside down to see the world from the opposite perspective. Good news: they meet in the middle.
You can read this book as either a buyer or a seller, but ideally, you'll read both sides to understand how your counterparty thinks.
The only ask is that you use this knowledge for good. Don't go ripping off the other side just because you know what they're thinking.