I recently created a printed circuit board for a raspberry PI design i’m working on. By the past, when I did such things, the cost to make it was not accessible for a home made design. In 10 years things have change a lot and now, you can do it for less than 100€ for a 10×10 two layer board. 4 layer is also something accessible.
I want to share with you this experience, because, I had a good and an bad experience to share.