Does this look correct for installing vinyl siding trim?

As long as that top piece is overlapping the bottom piece then it is correct. If they are just butt together then it is wrong. I have never used any caulk on those seams.

they should NOT be caulked but overlaped as stated. Reason is thermal expansion ,,,they move slightly with weather changes,,,let them slide. Are you doing this yourself?Or supervising others?

Its a contractor doing it. But, he admitted to me he's just started back doing it after 2 years of having another job. He has a foreman coming by to check his work daily though. Yes they are both overlapped.

thank you

the lap is corrrect though it looks like the two peices arent running straight. the upper peice looks like its tipping to the left

i think it would be advisable to run tape around the window frame,where it hits the tyvek. if any water gets past the siding, it may suck under the window frame there. i think folks recommend caulking or gaskets under a window like that, too.

Self sticking window tape get installed around the windows and door trim.
Make sure they install siding blocks any place there, lights, outlets, split blocks around any outside faucets, and a flush siding block where any cable or phone boxes go.
Do not let them just run screws through the siding!
Can you get a few picture of around the window? Something looks very wrong.
Was there something like 1 X 4 wood trim around that window and they removed it?

Is this a two story home? I ask because if it's a single story home there should be no need for pieces on your corner. They should have been able to install one continuous piece making for a much neater looking job.