Cloud Functions are priced according to how long your function runs, how many times it is invoked and how many resources you provision for the function . If your function makes an outbound network request, there are also additional data transfer fees.
Read moreIs cloud firestore expensive?
Although Firestore is very affordable with little usage, costs start to increase as you begin to scale. In most cases, the cost of using Firestore at scale is more expensive than other providers .
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