Read "Winning Through Intimidation" by Robert J. Ringer. Especially the part about the Three Type Theory!!!
a. There are only three types of people in the business world
i. Type 1: Lets you know that he’s out to get all of your chips. Then he tries to do just that.
ii. Type 2: Assures you that he’s not interested in getting your chips. Then he tries to grab all of your chips anyway.
iii. Type 3: Assures you that he’s not interested in getting your chips, and honestly means it. However, in the end, he tries to grab all of your chips anyway.
b. In business, no one ever does anything for anybody else without expecting to gain something in return.
I have 25 years in successful business and human nature supersedes all "rules" of business, even in this new age, so always be prepared and given the choice always go for type "1". They are the best investors of all because you know what you are dealing with.