Smashed ipad mini now it wont turn on, what needs repairing?

Basically I was at a BBQ with my friends last week and I was taking a selfie with my friends iphone 6 on a selfie stick when my friend knocked the selfie stick. The iphone fell and landed directly onto my ipad mini, when I got home I then plugged it in to charge over night but when I woke up still nothing happened. I plugged it into itunes and itunes never detected it.
I want to get it repaired because I assume thats cheaper than buying a new one as my mum still doesnt knos anything about that accident because I dropped my phone in the toilet a month ago so im scared to tell her, so I want the cheapest price possible so I can pay for it without my mum finding out. My promblem is that I dont know what needs repairing, obviously the screen does but do I need an LCD or battery replacement? Also is it cheaper to repair it myself instead of sending it off?

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