Digital-Tutors: Unreal Engine 4 vs. Unity: Which Game Engine Is Best for You?

[ryanjon2040]

One question. How much do you have to pay, to get full source of Unity ?

From their FAQ:

We license Unity source code on a per-case and per-title basis via special arrangements made by our business development team. As this can be quite expensive, we do not generally license source code to smaller operations, educational institutions, nor to companies in countries which do not have adequate legal intellectual property protection.

Why You Probably Don't Need a Source Code License | Unity Blog