Funnels make attribution harder: the opt-in, the order form, the bump and the upsell are separate pages and sometimes separate domains. BrainyMetrics listens to ClickFunnels 2.0 directly.
Every paid invoice becomes a sale, renewals (service period 2+) are marked recurring, and line items, tax, shipping and discounts are kept along with the funnel and order page. Identified contacts become leads, so opt-ins count even when nobody buys. Buyers are matched to their ad click by email, which tracko.js captures on your funnel pages; a hidden tracko_vid input gives an exact browser match.