My phone is dead

Okay so long story. My phone was in my pocket and i tripped hard and fell, and when i saw my phone next it had a huge dent right beneath the camera on the back side and it wasn't turning on.

I tried hard resetting it (power + home button) but nothing happened. It wasnt charging it wasnt doing anything.

After googling i realised i probably damaged the motherboard. I gave it to some local repair shop and he said the power ICU was damaged and that he would replace it. I think he repaired the broken one. Anyway he told me if i damaged the phone again it would not be repairable. And that i should sell it asap.

The phone was working flawlessly and it had my iCloud and all my data as if nothing happened.

THEN i dropped my phone again. It would notstart again. I gave it to the same guy and he said theres nothing he can do about it now. And that i should replace the logic board.

Anyway so i connected it to my computer and suddenly the apple logo came on for a few seconds and then vanished again. iTunes was detecting it but it gave me an error saying 'restore icloud' or something along those lines. I clicked that option but after the whole process nothing happened. phone was still dead.

I gave it to another repairman and he couldnt fix it either. When i got it back from him itunes wouldnt detect the phone. I have a feeling he further messed up the phone/ stole parts or something...

Currently my phone is dead (it has some weird horizontal greenish tinge in the lcd) But its completely dead. iTunes wont detect it. It wont start.

Do you guys think that if i buy a new bare logic board and replace the old one it could fix the problem? Any other suggestions? I really miss my iPhone so any help will be greatly appreciated :)

Thanks :)