Tinker is pretty cheap. Prime Intellect if you want more flexibility.

unsloth for small use cases, tinker for enterprise level use cases?

I haven’t used their platform so can’t speak to this, but super brilliant team and big fans of their work overall!

I would not say cheap per say, but in the context of "where is the business success going to be" that's one of the reasons why Mistral focuses on providing tuned model on premises to their customers.