How to avoid driving your car into the front garage wall
I drive a large bakki (pickup), and it only just fits into my garage at home. I have found many complicated solutions to preventing this problem, some simple and some very complex (even involving lasers).
Here is what I have been doing for years. It took about 10 minutes to set-up, and it is really easy. All you need it a piece of string, and a small piece of soft wood.
Hang the wood from the rafters, ensure that it just touches the front window. Now when you park, drive slowly until to just touch the wood. And no, the wood does not scratch the window (I used pine which is very soft). Alternatively, use a tennis ball if you are worried about scratched.