Return To Sender letters from DM Campaign

[Ryan Billingsley]

I would like to maximize the DM Campaigns we have currently before we pull leads again.

I was wondering what most people do with all the return to sender letters from the DM Campaign?

I have all different types from :

not deliverable as addressed

forward time exp

return to sender no such number

return to sender refused

return to sender vacant

I have 140 RTS letters and would like to squeeze another lead out of these.