Allotment etiquette is that you leave stuff on a vacated plot for the next tenant, unless the retiring plotholder offers it to you. If you are leaving your plot and want to give items to other plotholders, you can always tell the rep, who will find things a good home.
This plotholder would like her aluminium and Perspex cloche, glass & aluminium cold frame and water butt back please - she intended to take them and use them at home. If you are out there feeling awfully embarassed, please return the items to the plot and they will be taken home.