How should you make a difficult purchasing decision

I'm not sure whether you have any options since you didn't write any, but I will try to help you nevertheless.
First off, you should think about whether you truly need that very expensive thing. If you can manage without it, and want it only to prove something, the chances are you don't really need to have it. 
Secondly, you should see whether you can afford it - if you can buy something that expensive and not feel sorry about it (and can pay your bills and food and everything without a problem), then you may buy it and be happy about your purchase.
Hope this helps!

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