That is a really good rule! Thankfully I haven’t needed a rule like that because crushing poverty kept me from acting on my uke-buying impulses. 😂 “Food, or ukuleles?” It was sometimes still a hard choice. The most extravagant thing I bought on my own was even before the pandemic, the banjolele.
After watching many of the live lessons on topics like this, I do see the value in upgrading to more quality ukuleles eventually, but I have at least one for now–the one I won from here, lol.