Duplicates are the defining problem
Consumers comparison-shop across many channels, so the same person legitimately surfaces more than once. Buyers still will not pay twice, and duplicate windows are usually enforced network-wide rather than per campaign. Suppression hygiene across your dialer is the single highest-leverage thing you can fix in this vertical.
Geography follows rate competitiveness
Carriers can only win where their rates are competitive, which varies sharply by state. That is why auto insurance campaigns are almost never national and why state targeting is a hard filter. A transfer from outside the target state is non-billable regardless of consumer quality.
Shared versus exclusive
Exclusive leads go to one buyer and pay more; shared leads go to several and pay less. Both models are common here. What matters commercially is knowing which applies and, for shared, how many buyers receive the record — that number materially affects conversion and should be published.
Qualification basics
Typical criteria are current coverage status, vehicle count, driver history and state of residence. The underlying question is whether the consumer is genuinely in market rather than idly curious, which is what separates a billable transfer from a rejected one.