A deluxe, dry-lined, rendered garden/workshed/garage?
This is being built to the same standard as a house extension.
Expect to pay similar prices, and remember to install good doors and windows.
Otherwise there will be absolutely no point in insulating the walls - the wind will blow through.
Put in some power points as well to allow for a portable heater and a decent south facing double-glazed window.
Letting sunlight in on a dark finished concrete floor slab actinh as a heat sink might go some way to preventing moisture build up.
FWIW
ONQ.
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