Extensive water damage, advice needed

Hi- Last night my iPhone was damaged after accidentally being submerged in a sink full of water. The phone was going hectic, was working after a while but became increasingly difficult to work with, and shut down. I put the phone in a bag of rice in the hotpress for 10 hours or so, and the phone powered on, with obvious water damage on the screen and difficulties. The phone then faded to a dark screen and was put in the hot press for more time.

At this rate, the phone will charge (Vibrates when plugged in) so I am desperately hoping it can be revived - And yes I am aware of my mistakes in treating the phone after water damage..

Any advice is welcome - (I have contacted someone who can replace the screen, but I need another opinion before making the journey to get it fixed, in case it is hopeless.)

What is recommended is the cheapest way to get this repair (Without having to do it myself)? - i.e good, reliable websites?