I pay £26 a year for a full plot, about 30m by 15m. Love it, keeps us in veg all year (family of 4)
Its only about 500m from my house, which helps a lot, prob spend about 3 hours a week on it, more in spring/early summer.
I've just put up a 30m by 20m poly tunnel in the garden, so might let some one else take on half my allotment this year, as theres
a big demand now, the waiting list is some thing like 18 people at the moment, and when i took it on 4 years ago, half the plots were empty.