There are several brand new lengths of materials here incase that’s noteworthy.
Enough in fact, to do another house by the look of it... He is using your deposit, to fund the next job.
There are several brand new lengths of materials here incase that’s noteworthy.

Downpipes have not been fitted with an end elbow
If they weren't there before and there was no issues, I wouldn't bother.Debatable, but soffit vents might be needed, to provide some airflow. These things -
If they weren't there before and there was no issues, I wouldn't bother.

No vents before.Here’s some before pictures for any debate ongoing about rotten boards and soffit vents
No J trim to hold soffit at wall side .

Consumer act says I must give him the opportunity to, but really lost confidence in his abilities.
How can I ensure that the work is done properly and any covered rotten wood is discoverable.