Difficult question. But look at the closest competitors and see what they charge perhaps? For example, take a look at Cockroach Labs, or MySQL InnoDB Cluster,

Difficult question. But look at the closest competitors and see what they charge perhaps? For example, take a look at Cockroach Labs, or MySQL InnoDB Cluster, or one of the many database as a service providers, or whatever you think is the closest competitor, and see what their licensing terms and pricing are...