AUSTIN (KXAN) — As ACL begins, you may see a few new faces at your neighbor’s Airbnb.

The homeowners that rent these properties out may be breaking the city’s rules.

Earlier this year, the Austin Code Department found at least 75% of Austin’s more than 10,000 short-term rentals are operating illegally.

Now, KXAN investigators learned that homeowners owe the city of Austin more than $108,000 in short-term rental violation fees.

Most of the violations have to do with the homeowner not having a license to operate an Airbnb, or advertising the property without a license.

When these properties aren’t licensed, Austin can’t collect hotel occupancy taxes when people stay there.

Other violations include occupancy issues.

“There are thousands, literally thousands of people who are not in compliance,” said Dana Brockington, an inspector with the city’s Code Department.

Brockington says identifying these properties is like a chess match.

The department uses a vendor to look for rental property violations but also learns about them from calls and complaints to 3-1-1.

“They try to get sneaky with the advertisement,” he said. “They try to hide their advertisement so you can’t identify their property.

On Friday KXAN rode along with Brockington as he visited home after violating home.

He says the Code Department issues a warning for a violation and gives the homeowner at least 10 days to fix the violation.

After that, the first fine is $500.00, the second fine is $750.00, and the third fine is $1,000.00.

After that, the city will take the homeowner to court.

Brockington says some homeowners continue to break the rules even after this point.

“Some people look at it as the cost of doing business,” he said. “If they can make a few thousand dollars during the month, they don’t mind paying the 300-dollar fine.”

KXAN’s Anthony Cave contributed to this report.