You might think that the activity of buying and selling is a simple activity. You might say that it's just a matter of buying or selling a product at your desired price. But the activity of buying and selling is actually complex and there are time tested concepts and theories already that can ensure your success in buying and selling. Do you know these proven concepts and theories already? If you don't, this good would be very helpful to you. If you do, then this book can at least refresh your real life knowledge and experience and even improve it...