It does not look clean If they tabbed them correctly it could be correct , but I would

have mitered the corners

I think you chose the wrong style of casing for a j channel type siding and the depth is not idea. At this point you are in a difficult spot.

Thank you for your response. Totally agree with it not looking clean and agree with the mitered corners! Thank you again.

+1. I agree on the mitered corners. With that said, as Todd also mentioned, that doesn't mean that this is done wrong. We'd need shots from the backside to see how its put together.

Thank you for your comment, unfortunately don’t have pictures, but they did show me the back and how the tabs were done to drain the water, so I guess I believe it was done correctly in that aspect. Just was more looking for advice on if it is common to have a finished look with mitered corners or it is common to just leave the straight cuts. I was told by contractor they don’t do mitered corners and in all my research regarding j channels, they talked about mitered corners?

looks ok.

Not pretty, but if done properly...functional.

They could a little trimming and and a little shimming to clean up the lines.