sending thank you letters to people i cold call?

[Devin Mann]

so im calling around a listing that i put up for 600k.

i have about 50 people whoi spoke with from cold calling. none of them know anyone who wants to move into the area, and none  of them have any interest in selling.

should i send them a thank you note saying thanks for speaking with me?

does this generate more business even though they said no?