One more thing ive learned in business: kiss ass. Act like your client or vendor is the most valuble person in the world and deserves all the worlds attention and pampering. THIS is how you get people to do favors for you, not by believing you are entitled to it, but by convincing your client or vendor that they are entitled to YOU.
If you want to succeed, make then feel special. If they do not feel special, you are just another grain of sand in the proverbial business landscape.