Licencing question: Documentation show one thing, installation suggest a huge ($) diference

I am trying to figure out what licencing model I must subscribe to. If it is some multiple "logmein pro"s ora single "logmein central" subscription.

For exemple: I need to remotely controle 20 computers simultaniosly.
Does one single "logmein central" pay the bill or I will have subscribe, for each one od the 20 computers, a individual "logmein pro" licence as well?

In a "central trial" licence, when installign the msi on the computers, the instalation keep showing only a "pro trial" licence do choose to select from. Very confusing.