There are four collectors: Totti, Pictor, Donni and Bagio
Pictor, Donni and Bagio charge 10% of what they will gather. Fortunately their rates don't increase with your Hall bonus.
Totti works for free (he enjoys shaking down people), but will only work 10x a day, then 10x at his tired rate, then will sleep the rest of the Day.
Donni always makes 70% of Bagio in 12 hours.
Pictor makes 41.75% of Bagio in 4 hours, with some rounding errors.
Totti follows his own pattern, adding +10 coins until tax level reaches 1000, then only adding +5 coins for each further increase in tax level.