When Sweet becomes Sour

I was presented with a potential piece of work recently.  That's a nice thing when it happens.  At a minimum, it reinforces that you're still needed.  However this was disingenuously offered.

What was initially characterized as a very short term piece of work, had a large amount of background development and foundational work needed. Despite reassurances it was only small when I began to look into the job it wasn't small, it was big.  All this after initially indicating my own agreeableness to the idea.  The catch here is that the time available to prep was small, and the return for that work was also small.

So, I went back and said no thanks, citing the truth that I didn't have a week to put into the preparation. So all is fine.  Except it's not really.  I feel like I was taken advantage of, and taken for a fool.  The experience left me with a very bad taste in my mouth for that organization.  I don't think that was the intent, but in some situations the reality of how something is handled is more important that what it is.