#2. If you feel your helping someone out once with a price there is nothing wrong with that either! You may be suprised by this person and they could lead you more work. (GOD works in mysterious ways!) But you should tell them that you are reputable business and since you are giving them the best deal around and for that matter you will need to payed for the work the day of the job or before. No questions asked.
If you feel you are doing the right thing by "Helping someone out" well good for you... but do not get screwed over doing it... there is not a worse feeling in this business!