Creation of proprietary software using free licenses

Question

open source

Greetings.
There are several classes (php) that are well suited for developing a proprietary product. The classes come under Apache 2.0, MIT
With MIT it is clear - we use it as we want (we leave a note about the author in the file itself).
What about the Apache license? Of the additional conditions - in the root directory to keep files LICENSE, NOTICE. But what to do if there is not one but several classes with this license, whose NOTICE should be taken or combined?
And how then to notify that this is a proprietary product, if you need to leave the APACHE license in the root LICENSE?

And what to do if development is on order, let's say a script is written to systematize image files, but as an element of the script, a class is used to apply watermarks (apache license). Or in general - is a template for sale being made up and a library for a gallery in javascript under apache license is used?
// example not from real development

Answer 1

And just make the Credits directory and there, in the subdirectories with names corresponding to the products, is it impossible to place all the licenses, in the root of the project, put the file that all the copyrights are there and there.