Vinyl siding

[ccurrins (Christopher Currins, CMI)]

@ckratzer

The only thing wrong with it is the siding may be cut a bit too short. The siding should be cut about 1/4" shy to allow for expansion and contraction. If it’s cut too wide or if the siding has shifted from side to side the gap your photo shows will occur.
The window in the picture is of the type that has it’s own built in receiving channel and therefore requires no “J” . What you see in the pocket of the receiving channel does ,in fact, appear to be flashing.
If the flashing had been stuck on just 1/4" away from the angle of the pocket the installation would have looked much better.

I disagree. The window casing should be flush against the side of the house, with J channel then applied to the side. There should not be a 1" space between the trim and the side of the house. This would allow snow, ice and everything else to to get behind the casing.