If you want to ensure she won't regret the choice, go shopping together!
You will pay extra, as in you will pay more than the ring is worth. If you buy a diamond ring, turn around and try to sell it back, they'll give you something like 30% for it.
Also, listen to this: http://freakonomics.com/2015/04/16/diamonds-are-a-marriage-counselors-best-friend-a-new-freakonomics-radio-podcast/
You will pay extra, as in you will pay more than the ring is worth. If you buy a diamond ring, turn around and try to sell it back, they'll give you something like 30% for it.
This has always struck me as such a strange argument against buying a diamond ring, because it's true about every retail purchase. If you buy a chair, then turn around and try to sell it back to the store, you'd be lucky to get 30%, but no-one thinks that's an argument for sitting on the floor. You buy a chair because you want to sit on it, not as the start of a complicated chair-r...
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