SMS Text
marketing.
Let me run down a Scenario.
Customers pull up to your wash and see a sign that says "text wash to 74455 for our VIP list" once they text the customer gets an immediate reply with a coupon code for your choosing (1/2 price wash).
You will continue building your VIP list. At any time you can Text all of them on the list. if you are slow on Wednesday afternoons Text a special for Free xyz. etc....
Believe it or not it is much less than Val-pak or any form of print that I am aware of.
-Derrick