Thank you to everyone for their replies.
My observations where the same, shingle deterioration, granule errosion, cupping, curling, valley detioration and water stains.
The home is approximately, 11 years, but not verified. Most likely the shingles might be a contractor’s grade 15 year shingle, but unknown.
Regarding the water stains on the roof sheathing, a gap exists where there is an intersection between an upper gable end overlapping the ridge of a lower hip roof, picture roof03 shows outer profile, (moss growth due to constant shade, north facing).
roof04 shows gap between sheathing and rafter, daylight visible when attic is in darkness.
The home owner is disputing my observation and is claiming financial loss on the sale of the home, due to my statement regarding the condition of the roof.
This is not an amusing situation.
Any more thoughts?