About seven months after taking over the property, the new owner - who was also the complainant in this case - was notified by tenants the mould had returned.
Evidence presented to the authority also showed the tenants, who had remained in the home between owners, knew Mr Hendriks had seen "the ceilings in the upstairs living area were very obviously black with mould" when he first visited the home in September 2011.
Mr Hendriks, who admitted doctoring the mould from the photos, told the authority a property inspection he carried out in "a usual and reasonable manner" failed to reveal any of the problems identified by the complainant - including mould and damp issues in the downstairs area of the home.
However, reports supplied to the authority by the complainant indicated the water ingress in the downstairs area had been present for some years and had been concealed by recently applied paint.
Chris Rogers, the chairman of the authority's complaints assessment committee who assessed the complaint against Mr Hendriks, said alteration of the photographs was "misleading and obviously unsatisfactory".
However, he disagreed with the complainant and stated in the decision Mr Hendriks did not seem to be aware of water ingress problems in the downstairs area of the property.
Mr Rogers also said a complaint against another real estate agent, who was the second licensee for this property, had been brought before the authority.
The complainant believed the second licensee misled her into believing two other prospective buyers were interested in the property, pressuring her into making an offer at the asking price.
There was no evidence to show this licensee engaged in unsatisfactory behaviour, Mr Rogers found.
A separate hearing will take place to decide if any orders should be made against Mr Hendriks for engaging in unsatisfactory conduct.
