Hey guys, I've been reluctant to post about this, but its been bugging me for a long time. My next door neighbor and close friend is quite a bit younger then me and she asks the question a lot. At first it didn't bother me, and then I thought she was just curious what things cost since she is young (19yrs old) but now it's getting ridiculous and annoying to the point that I hide new purchases from her so that she wont ask me "OMG!! How much did you pay for that??"
It started out small, asking about things like books and then she started asking about other purchases like large appliances and more recently she asked myself and MY MOTHER what our credit limit was!? I find this really inappropriate and it makes me very uncomfortable, I've tried to say things like "the price doesn't matter" or "its not really any of your business" but she just keeps probing. I almost feel the only way to get her to stop is to be very rude to her.
I've been pretty successful with just hiding new purchases from her the last few months, I purchased some exercise equipment a few months ago and it sits in the garage so she wont see it when she comes over

but I'm getting a puppy soon and I wont be able to hide that from her at all for obvious reasons, I'm tempted to lie and say I bought it from a pet store instead of a breeder or maybe say I adopted it from the humane society. But I hate having to lie to her.
So my questions are, am I crazy? Is this inapropriate? Have you ever had a friend do this to you? How did you deal with it? How would you deal with it? She lives right next door so I can't really ignore her without ending the friendship.
Thanks for your help!