Neighbor roof leaking and asked me to split the cost
We live in a semi detached house.
Our neighbor hired someone to remove the ice on their side of the roof (close to our side).
While the person was working on the roof, he knocked on our door and asked if we could split the cost.
I initially said yes because he claimed the area is at the center between our house.
But when I go out to talk to him, the leaking point is at least 1feet from our side's exterior wall.
I've checked our room next to their leaking area, it was totally fine.
I'll be going up to the attic tomorrow to check if there's any trace of water leaking in.
My question is,
1) if he hired someone to do the fix without consulting us prior, do I have the right to reject to pay?
2) if I don't find any leak on my side, do I have the responsibility for the fix?
3) does he have to proof the damage is related our side if he wants us to split the cost?
Thanks in advance for any advice.