A used mirrorless camera can be a better deal than a cheap new one when an older enthusiast body offers stronger controls, in-body stabilization, a better viewfinder, or weather sealing at a similar price. Roughly £220-£600 can cover many capable previous-generation APS-C or Micro Four Thirds bodies, while inexpensive new body-and-lens kits commonly start around £390-£860.
Condition and system support determine whether the saving is real. Inspect the sensor, lens mount, screen hinges, card slot, ports, battery compartment, and stabilization mechanism; test mechanical and electronic shutters, continuous autofocus, video recording, USB operation, and every control. Also confirm that batteries, chargers, firmware, RAW software support, and the lenses you need remain available.
Choose new for a warranty, predictable battery condition, current connectivity, and dependable returns. Choose used when the seller permits testing or returns and the older body adds a feature you will actually use, but include the cost of a replacement battery, charger, sensor cleaning, and the correct lens in the comparison.