
How much did you spend on (expensive new item)?
Comparison is the thief of joy. There is no benefit to finding out how much your brother-in-law spent on his fancy new car, unless you are considering buying the exact same one. Otherwise, it's only to feel smug that you've "done better", or disappointed that you're not "measuring up". Neither are necessary emotions.
When are you having a baby?
This is the question couples everywhere dread hearing. It should have died out of our social conversation years ago, but still everyone - from family members to complete strangers - find it appropriate to ask (mostly newlywed) couples when they're planning on producing life.
There are several things wrong with this question. First, the assumption that having children is a matter of when, and not if. This might shock some people, but not everyone wants to be a parent - and that's totally okay.

For some people, the desire to be a parent is complicated by other heartbreaking circumstances - illness and infertility. Just because a person hasn't disclosed an issue to you doesn't mean there's more to a situation than meets the eye. Why rub salt in the wound?
Then there's the inherently sexist nature of the question, which is more often than not directed at women. There's an assumption something is wrong with a woman who, God forbid, wants to focus on a career or her own life, rather than reproduction. There's nothing wrong with her; the issue is you. Stop seeing women as wombs on legs.
When are you getting married?
The only exception to this is if the couple is already engaged and you're curious about the date. Otherwise, it's an invasive and unnecessary question. (I can hear parents everywhere gasping).
Again, not everyone wants to get married. Not every couple is ready for marriage. And no one knows the ins and outs of another couple's relationship. Leave them alone and let them announce an engagement when, or if, it is the right step for them.
Do you have a job yet?

If someone has recently graduated, quit their job or otherwise found themselves out of work, it's natural to want to know what's next for them. But asking this question can add unnecessary pressure to a situation.
If someone wants you to know they have a new job, don't worry - they'll tell you. Otherwise, leave it alone.