Firestore’s pricing model is based on operations performed, storage used, and network usage. Operations are categorized into reads, writes, and deletes. Each has a cost associated with it. Storage costs depend on the amount of data stored in Firestore. Network costs apply when data is transferred out of Google Cloud.
To minimize costs, design an application that optimizes read/write operations. Batch multiple operations together to reduce the number of transactions. Avoid frequent small reads/writes by fetching/storing larger chunks of data at once. Use queries efficiently to retrieve only necessary data, reducing read operations.
For storage, regularly delete unnecessary data or move infrequently accessed data to cheaper storage options like Google Cloud Storage. To reduce network costs, keep data transfer within the same region as much as possible.