Power supply make or buy

[Ben N]

This power supply kit/pcb looks well done to me.  240v though.  You would need a different set of transformers if you lived somewhere that doesn't provide 240v

https://guitar-electronics.eu/en_US/c/Power-Supply/102

Looks good and reasonably priced for 4x9v/420ma fully isolated, regulated, keeping in mind that 420ma can feed a lot of analog pedals on a daisy chain, or a single digital monster.