The Ballarat Magistrates' Court was told Robert Beames, 48, saw the man and his son who used to live with him outside the building in September last year.

A verbal altercation occurred, before Beames threw the victim down stairs onto the footpath and attempted to punch him. The victim's son threw coffee on Beames, which "antagonised" him - he chased the son away, and continued attempting to punch the victim.

He landed one punch to the victim's face and he also left a "medium dent" in the man's car with his knee.

The victim's son phoned police and Beames left, later reporting to the police station and making a full admission.

No one was injured in the incident.

Beames had taken issue with the victim over unpaid rent, and allegedly taking an item belonging to his daughter, the court was told.

He pleaded guilty to two charges of unlawful assault and property damage.

His defence lawyer said Beames had been diagnosed with post-traumatic stress disorder, and while he was on a community corrections order at the time, he had completed 200 hours of unpaid community work.

Magistrate Ron Saines said it was an example of public and "extremely inappropriate" violence.

"You are a candidate for imprisonment if you allow yourself to be drawn into any more violence," he said, noting Beames' "serious history".

Mr Saines added Beames did plead guilty early and made full admissions.

He was sentenced to a 12 month community corrections order and must complete 100 hours of community work.