Hattrick X-Files is a website with different handy tools for Hattrick. They’re not free, but it’s often possible to ‘test’ it. I won’t mention them all. The most useful tools are:
“Arenasizer“, which helps to calculate the optimal size of your Arena.
“Coach“, which calculates the costs of transforming a player in a coach or buying one.
“Spokes“, which calculates your optimal number of spokespersons.
Give it a try!