How to say no to a perspective client?

Gut instinct rocks!

First sit down an make notes to yourself about why it doesn't feel right to you. Look them over an then add words like your a great person but,.....or maybe you wanna say.....with all the things life is throwing at me now, my spare time is limited,...............you always wanna take anothers feelings into thought, for you never know when you my be on the receiving end. Hope this helps you an good luck.

You don't have to go back, just make a phone call and tell him that you have decided the project isn't right for you due to time demands, skill-set or other reason. If possible provide other contacts for him.

walk up close to him, gaze him in the eye, sigh, then simply say, John, i never thought it would come to this, i thought you and i would have a relationship that would last forever, but sadly, it was not meant to be, i bid you farewell, then take your right knee, moving swiftly into his ballsack, then say NO JOHN, I DONT WANT ANY CRYSTAL METH, BACK OFF YOU ******* TWEAKER