PCBs are super cheap. If you design one which is of a common type - 2 or 4 layer, FR4, 1.6mm etc, the price per unit is very low. There's lots of Chinese board

PCBs are super cheap. If you design one which is of a common type - 2 or 4 layer, FR4, 1.6mm etc, the price per unit is very low. There's lots of Chinese board houses now that will produce 100x100mm boards for 50c a board if you buy 10! That's $5 including postage to have a double sided PCB made. 4 layer is slightly more expensive at lower quantities, but once you get more than a few hundred made you're looking at under $1 a board. If you want to make a product cheaply, doing it in a way that makes use of the electronics production process is a really good way to start. Compared to implementing your own mechanical designs and manufacturing process it's really, really easy and cheap.