There have been several articles over the years. Since there 80s there have been over 200 liens placed on various Trump owned companies. I think they ranged from like tens of thousands of dollars to over a million bucks.
He's also been cited for failing to adhere to the Fair Labor Standards Act a bunch of times for employee wage and hour theft.
The one that sprang to my mind was the architect that did some work for Trump, devoting all of his small companies resources to a job that Trump didn't pay on. I think he put the dude out of business (or nearly did so). I'll see if I can find it.
[Edit:
This article is the first one that came up and has several examples.]