I'm interested in seeing the behavior of prospects before they become customers. This could include one or more visits. Once they do become a customer, we place a non-PII customer number in an eVar every time they sign in. The main way we can tell who customers are is by seeing if that eVar is empty or not. The issue is that we are having trouble specifying before the eVar is populated.
Any ideas on how to set up a segment for that? Is it as simple as this?