We now have the garden shed which may just house the garden tools and a lawn mower, or even a workshop but could well become your own ‘retreat’. Because the walls are usually timber it is easy to build the base boards around the outside with even a lift out section for the door. You would, of coarse have to sort out alternative storage for the gardening tools & mower.
If this is your favourite then best get yourself a new shed to the dimensions that will fit in the garden.