Would you like to know a good way to cut off your chance of earning my business before the contract is signed? Be sneaky.
Along the same lines of over-promising and under-delivering, the sneaky individual is notorious for sneaking terms into contracts that put the client at a major disadvantage, contrary to negotiated and agreed upon terms. The hope is that the client won't notice until the contract is signed and they are "locked in" to the contract and the terms contained in it.
The fact that these types of people exist in our industry is the reason I'm thrilled that I took a contracts class in law school. It's a pain to comb through mind-numbing legalese in order to make sure every term you're looking for is spelled out correctly, but it will do two things for you. First, you'll be able to make sure everything is accurate and you're getting what you're paying for. Second, you'll flush out a sneaky rep and kill a deal that will likely cause nothing but problems.
As an example, a year ago I was negotiating a media buy with an individual at a rep firm. Although I had worked with the firm before, I had never worked with this specific rep. We spent quite a bit of back and forth time going over the media properties before agreeing to one specific network containing a handful of properties. It didn't take very long while looking at the contract that the rep had swapped out the agreed upon network and replaced it with an inferior media property for our specific needs. When confronted with this fact, he simply stated that the agreed upon network didn't accept the negotiated CPM rate, so he put another network in the plan instead. Infuriated, I didn't sign the contract and haven't worked with this rep or his company since. In addition, I've advised others to steer clear of this individual.
All it would have taken was the rep to come back to me and let me know that he had a snag with the original network, and he would have left the door open to doing business with me in the future. Trying to sneak something by me not only hurt his own sales opportunities, but it has taken away business from his company.