And over the last two years there have been a number of smashed windows.
The insurance excess for the property was now so high Mrs Wilkinson expected they would have to pay for the cost of the latest repairs.
"It's extremely disappointing that people have nothing better to do.
"This is wilful damage of others' property and hitting an organisation that has no money. Now we have to divert money for services for older people in the community to pay for the damage. It's so wasteful and unnecessary."
She said the incident had shaken her feeling of safety. "I feel unsafe again and come to work each day anticipating problems. What I'm fearful of was one of my staff members could have been sitting in that room and they could have been hit with a rock."