Gonna surprise my wife this month

Wow here my middle class parents had a combined income of at best 4000€/month before my dad retired. That's a huge difference I'm taken aback.

In much of the US the equivalent amount would be considered middle class. It all depends on where you are. But our taxes tend to be lower than Europe in general- so you have to make less money to have a “take home” of that much. Cars are also cheaper here and cheaper to own than much of the world, and it’s isn’t uncommon for people who make only 20-30k a year to have cars that cost half or even twice what they make in a year. There are entire industries that exist in reliance on people defaulting on cars.

I don't know the numbers but believe you about people buying things that are above their paycheck. However in that case you have to agree that half our twice your annual income represents a HUGE financial decision that you shouldn't take alone in a couple.

Personally, I don’t think major financial decisions should be made alone. But then again- often times they aren’t. Before buying an engagement ring for example (yes- I know rings are problematic and that is a whole other topic: but it’s still a reasonably common if foolish tradition...) a person will likely have discussed with their SO and the SO’s confidants- “felt out” what they want- if they want a fancy ring or not, type of stones, etc. I’d hope you’d know if someone you intended to marry was the type of person who’d rather save the money on a flashy ring or have a sparkly chunk of sentimental conspicuous consumption.

If one were going particularly up market- they’d probably find some way (using friends or misdirection) to get their would be fiancé to pick the EXACT ring they’d want- then the “surprise” isn’t the configuration of the ring- it is the delivery and the fact you got it for them. The same logic I am sure applies to cars, or surprise vacation trips and such. Namely that at the least there is probably some form of “discussion” indirectly to confirm the decision is desirable and livable to all parties.

But I do counter you this food for thought- chances are if you buy a car... you aren’t spending a third or even any large percent of income. You likely will pay credit, monthly. You may say it is the same- but conceptually... what’s the difference? Say that in your relationship you are given discretionary funds of $300 a month on average- video games, nights out with friends, hobbies, “beer money” and so forth. If you spend $300 a month for several years- it still Equals the same amount wether you bought $5 pretzels and $6 beers and $20 film tickets- or you are paying off a $25,000 vehicle. The major difference is in credit utilization... but if the decision is financially sound and you weren’t preparing for other major purchases or need to build credit towards a major purchase like a home...

Tl:dr- all I’m saying is different strokes for different folks. There are partners who would be thrilled to come home and find you got a new puppy, some would roll their eyes and lovingly accept it as “who you are” and others would be furious. For some of would depend on the dog or the breed or so on. So certainly one should know their partner and one should act accordingly in their relationships. But I don’t know that the “buying a car for a gift” thing is so fantastical. I’ve done this with USED cars for exes. Either way it’s my money- but that’s how finances in MY relationships are. Do whatever you want if the bills are paid and you can cover for mutual expenses.