My line is...

Oh, I'm glad you called. I have a time share in Arizona available for the 2nd week of August. I can let you have it for a low $1,500.00. The desert is so beautiful that time of year, and the temperatures are quite bearable in the evenig when the Air Conditioning is working properly.
Once they express dis-interest, tell them that you understand their apprehension, but by signing on, they are helping you to earn money toward a college education.