Anything too stupid to be spoken,” he asserted, “is sung. - Robert B. Cialdini

The truly gifted negotiator, then, is one whose initial position is exaggerated enough to allow for a series of reciprocal concessions that will yield a desirable final offer from the opponent, yet is not so outlandish as to be seen as illegitimate from the start.

The rule says that favors are to be met with favors; it does not require that tricks be met with favors. A

Be as precise as possible about your need for aid.