The message
from Victoria Clare contains these words:

What is the best way to ensure the base is sealed, without providing a path
for damp and rot? Do you just run the walls right down to the slabs?

If you make a poured concrete base, or lay slabs, it's well worth
making sure that the base measurements are very slightly smaller than
the outline of the shed, so that the walls have a centimetre or so
overhang all round and rain sheds straight off onto the soil (or a
border of gravel, to avoid mud splashes). If the concrete, or slabs,
protrude a couple of inches beyond the shed walls, rain landing on them
can run back or puddle under the shed causing the wood to rot.

I prefer a floorless wooden shed bolted onto a poured concrete base,
so there's nowhere for rodents or water to lurk unseen.

Janet.