Written on 7/13/26 by a human.
This is for me, so I don't know how much it'll help you! I'm writing this to layout a set of rules for the stuff I buy.
The first thing you need to think about when making bigger purchases is how long it'll last you. The way you can think that way is by asking yourself...
Will it be amazing today, yesterday, and tomorrow?
I feel like that phrase is very commonly used, but never for purchases, mainly for other big decisions. For me, this phrase means you need it to be a more modular product that won't need constant repair, but still has easily available parts and is easy to repair or upgrade. Also, it's really good if it supports a readily used standard (such as Matter, USB-C, etc) or is open-source/has open-source software!
You also really need to understand what you will use this for. If this product can connect your multiple hobbies or something like that, then get it. For example, I bought a 3D-printer a while ago, and later I bought a vinyl cutter. This allowed me to make custom Croc Jibbitz that can have anything on them because I can make a custom Jibbit shape and then put a sticker on it.
You don't want to run out of money because of your purchase. Try to not make too big of a purchase at once. Think about it for at least a month. That's all I have to say on that.
Think about what you need out of this product. Is it what you need? Does it fit all of your requirements? This is highly related to Step 1, so that's why it's barely anything.
This will expand over time like other things, such as the US national debt.