Anyway, you can set the prices of your service so that it is easy for everyone to know the prices of what you offer.
The price will be determined by the type of documents and the topics they contain.
In many of the projects I worked on, I took into account the approved budget, especially with start-up projects. Translating a site with many pages will not only be priced based on the number of words but also the time it will take to do so.
I will also allocate very low prices for students who want to translate scientific files that will help them in their research or in spreading awareness about a topic.