If you’re working on a Unity project with the free Unity license, you’re only allowed to have a maximum of 3 people (and a storage limit of 1GB) on Unity Collaborate Plastic SCM. While you can work around the headcount limitation by adding and removing members when needed, it can be quite a hassle. Hence, for those without a budget for a paid Unity plan, a cheap and easy way to go around both the personnel and storage limit is to use GitHub Desktop for collaboration.

GitHub Desktop for Unity — Part 1: Setting up your source control repository
This article is a part of the series:
Using GitHub Desktop for Unity collaboration