Documentation
Bill types
Bill type is not a label. It selects the playbook the agent argues from, and the three are genuinely different negotiations.
Cable and internet
Ask for retention by name, cite the competitor promotion in your area, treat the promotional rate expiry as the lever. The biggest concessions live on this desk.
Mobile and wireless
Argue on plan fit rather than threat: unused data, a legacy plan that has been superseded, multi-line pricing you already qualify for but are not on.
Medical billing
An itemised bill first, then charity care and financial hardship programmes, then a prompt-pay discount. Never a threat to leave, which does nothing here.
Pick the wrong one and the agent will still be polite and still get through verification, but it will be pulling levers the person on the other end cannot act on.