We use a credit system for pricing because of the variety in the lengths of essays and the time it takes to provide help.
We assign a credit value to each review based on the length of the essay. Each time you submit an essay of that length, we charge you the corresponding credit price.
Most students use 3 reviews (about 3 credits) for longer essays and 1-2 reviews for shorter ones. Students who get a video coaching call before they start writing typically don't need as many reviews.