I doubt there is anything on the exterior that would indicate if the car has AP, EAP or FSD. The only thing you can do is pm the seller and ask for a copy of the mvpa/receipt (with the identification stuff blacked out). If the car was purchased originally with EAP, it shows on the purchase agreement. If FSD was added later, it just shows up.
that's what vroom wanted to quote me a price. My menu options still say AP and SR+ even though I have a SR with no AP. Not sure what places like Carmax do?
I think the MVPA is the only way to know for sure. I'm not sure if Tesla updates it when you buy AP or FSD or just a separate receipt?