Do what we do. We don't get paid more for DECA, we offer it as an extra to our customers and charge them directly. "If you want this unit installed, i would have to run another line. It'll cost you..." As for the phone thing, run a new phone line! Bring your phone blocks and wall plates and say: "I'll have to run a new line. It'll cost you..."
This is CABL.com posting #320696. Tiny Link: cabl.co/mbvAG