Some couples see the money they earn as part of the whole, there is no my money and their money. It can make sense for some for sure, in my relationship its easier to just have our money, and it doesnt really matter where it comes from.

We also expect large purchases to be discussed first, outside of like presents and surprises of course.

Expensive is pretty subjective. Anything less than about $200 no discussion required. Above that, we usually have a courtesy conversation. We've never had a hard no spending if one of us really wants or needs something, but a required justification or notice prevents impulse buys.

Joint also doesn't mean you can't have an account (or a bucket or a tally) where you save for something you want, it just means it's not a secret.

Well if you have kids and/or need to budget as a household you kind of need to work together a bit to maintain that budget.

We just discuss these things and come to some sort of agreement.

For my spouse and I there is no "my money" and "their money". It is all our money.

If one of us wants to make a big purchase we have a conversation about it something like, "I've had my eye on a new graphics card. What do you think?" Then it goes either, "That's great. Have fun." Or, "Don't forget we have little Jimmy's orthodontist bill coming up." "Oh, yeah, thanks for reminding me. Maybe later, then."

I realize this isn't the norm and it took us a long time to get there. Many couples, my spouse's parents among them, argue over money and use it as part of a power play. We still have separate accounts for budgeting purposes, and around the holidays we have to be honest not to peek at bank statements and spoil surprises. But not having to worry whether you spouse is messing up your eventual retirement or little Jimmy's college fund sure makes life a whole lot easier for me.