I'm uncomfortable with personal questions, so I don't ask personal questions. If I am close with someone, that's a different story. Don't mind too much if someone asks how much I paid for something, but find it a bit tacky & rude. If I get a great "deal" on something, I'm always willing to share.
When I liisted my home, had no problem telling people what the asking price was. I go to realtor.com often. If you plan on selling, a realtor will tell you what the last one similar to yours sold for, when it sold & give you an idea of your market value. They can pull it up on their puter in a matter of moments.
When people ask questions like, how much do you have in the bank or what's your income, I regard it as being rude & nosey; & in all liklihood, those are the people who tend to gossip. Too much idle curiousity. That's just my humble opinion.