Here's a full set of both Metric and US wrenches. Blue Painter's Tape for Version 1 of the case.3 - M3 X 12mm Hex Socket Head Cap Screws.You will definitely need a dedicated mouse.
It depends on how you want to use/demo the tiny Mac. The keyboard is needed for setup and may or may not be needed when finished. Note that the project is designed around a specific display. There are plenty of cheap options out there. You can borrow a keyboard from your desktop. unless the applications you will be running need keyboard input.
The keyboard is only really needed for setup. Anything much longer would be difficult to squeeze into the case. You can use it to protect your Pi while configuring it. The small case is really not needed for the final project but is a nice to have.
