Pocket Watch help

Bad lighting most likely, the best shots are in soft natural light.

Can you open the back to take pics of the movement and inside of the case back? Don't force anything if you don't know how. Maybe it just unscrews - lefty loosey

It could be with that much, maybe less. Could be more if case is solid gold (my guess is that it is not solid gold - but I am still learning how to tell).

It looks like water or oil damage at the centre of the dial, that will take a bite out of the price. Price also depends on if it is working well. eBays sold listings will provide a ballpark of what it might fetch. If it was your dad’s, do you really want to sell it?