[ig1]

What you need to be thinking about is how different models affect incentives.

With your subscription model there's no way for the participant to work around you, but with a per-transaction based commission you need to think about how the participants are going to avoid paying you a fee.

If your drone vendors rely upon you for future work you could use the threat of kicking them off the platform to encourage them to be honest with you, but you'd need still need some independent way to verify if the transaction happened off-platform without them telling you.

Another approach might be to build a service (i.e SaaS) on-top of your marketplace that both sides of the market think is worth the commission-fee (it doesn't have to be SaaS, it could also be a traditional business service like escrow, arbitration, etc.).