A homeowner could be forced to demolish his garden annexe after neighbours spotted it advertised for £1,300 a month on Facebook - despite him claiming he built it for his own use.
Sandro Lechi erected the building at the bottom of his back yard in Bournemouth, Dorset, without planning permission.
He was then told to seek retrospective consent, at which point he submitted an application insisting the annexe is not used as residential accommodation.
However, eagle-eyed neighbours spotted the one-bedroom garden flat advertised on Facebook for £1,300 a month, before reporting Mr Lechi to Bournemouth, Christchurch and Poole (BCP) Council.
Planning officials have now refused the homeowner's application, meaning he faces having to demolish his garden property.
According to furious neighbours, Mr Lechi's Facebook advert described the annexe as a 'beautiful, newly refurbished ground floor flat for rent'.
He added the home features one bedroom, a 'spacious' kitchen diner and bathroom, and comes partly furnished with all bills included.
His neighbour, Rico de Gallo, said: 'It is advertised on a Facebook account.
Sandro Lechi built an annexe at the back of his house in Bournemouth, Dorset, without planning permission
Planning documents show Mr Lechi added a living area and kitchenette to a small, existing outhouse containing only a workshop and storage area
'This would seem to make it a separate planning unit. The ancillary building has been erected with all aspects needed to enable it to be rented out.'
Planning documents show Mr Lechi added a living area and kitchenette to a small, existing outhouse containing only a workshop and storage area.
Meanwhile, diagrams suggest the new annexe takes up a significant portion of the homeowner's back garden, which is surrounded by other residential properties.
Neighbour Karen Shiels said: 'The applicant states that these changes do not result in "independent residential accommodation".
'This is patently untrue as the unit has been extensively advertised on social media as a property for rent.'
She added: 'The so-called outbuilding has its own letterbox and could easily therefore have a separate postal address.
'It has been altered and furnished to be let out as a self-contained garden flat.'
Diagrams suggest the new annexe takes up a significant portion of the homeowner's back garden, which is surrounded by other residential properties
Furious neighbours reported Mr Lechi to the council after seeing an advert for the annexe on Facebook
Wendy Lane, director of planning, concluded the building would create an 'unsympathetic addition to the host dwelling', resulting in a 'poor design that would appear cramped and within the plot'.
She added the 'resulting intensification of the dwelling house would be contrary to the character of the area'.
She also found the garden flat would 'create unacceptable impacts on neighbouring amenity, with increased noise, more traffic movements and parking requirements'.
Mr Lechi has 12 weeks to lodge an appeal against the decision by BCP Council.
The Daily Mail has contacted BCP Council for comment.