how i can set a limit for users with a specific label to create a maximum number of documents?

Just like many apps have premium vs free users, and free users can use the app but with some limitations; i wanna implement something similar. in my app, the premium users have a label and the free don't. My plan is that, each free user can create maximum of 4 posts in a bucket, where the premium users can create as many as they want.
So i would need a variable in the DB, that no user can update. I also need to implement this checking if any user is creating more documents then that limit number

I could check the db for how many documents the user have already created, before creating each post. but this doesn't sound the perfect way to handle it, also not much secure. Can you think of any way to implement this feature securely within appwrite?