>We're not completely self-serve right now,

"right now", which implies that you plan to move to self-serve. and obviously manually checking in on each and every customer is not sustainable if you scale.

do you do periodic checkups now? hoping nobody lies during onboarding is risky, in an already-risky endeavor. have you thought about anti-abuse systems for when you go self-serve?

We do run checkups and keep very closely in touch with our customers. We don't plan to go self serve in the near future and will most likely still have a very personalized onboarding process.