There are other cameras for sale on the site, including ... a camera hidden inside a smoke alarm which claims it could be used to help "monitor" an "unfaithful partner". There was even a "bathroom ...

The second-hand camera lens market is currently valued at $2.5 billion (around £2.0 billion / AU$3.9 billion), with projections suggesting a growth rate of over 5.8% between now and 2023 ...