NC obviously.
DD14 phone recently got broken - total accident, not her fault (I saw it happen).
She needs a new one - fine. We gave her a budget to choose a reasonable one. Affordable.
She has her heart set on one that is a smallish amount (around £50) more than the budget we gave her. I said to her if she really wants this one then she needs to contribute the £50 herself (she can afford it).
She's had a total meltdown, saying she won't pay it and that we're being "tight". DP says we should just get her it as it's not much extra (we can easily afford it), but for me it's a point of principle - if it's not worth £50 to her then why should she expect us to pay the full price?
Also now that she's having such a strop about it I'm even less inclined to budge, as it will just teach her that this reaction works.
YABU - it's a small price to pay for your child's happiness
YANBU - if it's important to her, she should be prepared to contribute