I got a big box of postcards printed up 5000 for £99 (should last ages)
My normal flyer on one side, and space for there name adress and a stamp on the back, and a little message, along the lines of
Hi, its Daniel here from "the red carpet" im sure you will remember us we cleaned your carpets for you some time ago
I hope you are well, just sending some cards to our previous customers just to remind them of our services in case theres anything we can do for you, or if you no of anyone who could use our services.
Also offer a £10 reward, but no one seems to want it.
Every old customer gets one of these every couple months
These are working very well for me