I retired at 64 that's 6 years ago. About 2 years before we (my wife and I) built a kit cabin 3.5 metres X 2.5 Metres in the sloping garden on a deck in 2 weeks, electrics, heating , sorted out Ikea shelving & chairs, DIY store table various lights, a home made spray booth with fan to the outside and Ikea Billy bookcases with glass doors. My production has gone through the roof. A kit built in 10 days, even with home printed decals, cast surfboards etc. Retirement is superb!
So three hours in the morning and 2 hours in the afternoon, 5 days per week. Weekends off, just like work!