I have a mate who retired (not through choice)at 65 as a window fabricator, he hated doing nothing so started a small window round, him and his wife did it for a few years till she got very poorly so he sold me 90% of his work keeping back a few bungalows to “give him something to do”
After his wife recovered his round just kept growing.
He is now back to 5 full days a week, on ladders in all weathers. He is 74 and looks fitter now than he did the day they kicked him out of the factory at 65.
I keep telling him its time to give in coz I want his work ha ha