Default [Q] Samsung Galaxy S4 Front Glass Cracked and Digitizer broken

I was siting down yesterday afternoon with my Samsung Galaxy S4 GT-i9505 in my right tracksuit pocket I stood up got a text and took out my phone to check and I see the screen is cracked and is not displaying anything apart from the top third of the screen. I've been to a shop and they said it'll cost 145.00 to repair and Samsung UK said it's not covered by warranty and I'll have to pay a similar price at a service centre. It was bought off eBay last summer and is not on contract although I am a T-Mobile UK Pay As You Go user. Is there anyway anyone would know to repair it for cheaper or even possibly free (with some sort of warranty) as I'm just a teenager.