A few months ago, I finally built my own board from scratch. I used an Arduino-alike (based on one of the bigger Atmega parts)
It was an interesting endeavour-- designing a PCB, mounting plate/casing, sending them out to be be drilled, soldering it all together, configuring QMK firmware. It's the order of something like assembling Heathkit audio gear was in the 1960s-- the finished product is on tier with a good quality commercial product, but you also get complete control over any substitutions and customizations you like.
Unfortunately, due to low economies of scale, I paid about $500 for the board.
It was an interesting endeavour-- designing a PCB, mounting plate/casing, sending them out to be be drilled, soldering it all together, configuring QMK firmware. It's the order of something like assembling Heathkit audio gear was in the 1960s-- the finished product is on tier with a good quality commercial product, but you also get complete control over any substitutions and customizations you like.
Unfortunately, due to low economies of scale, I paid about $500 for the board.