How do I find out who called in a complaint to code enforcement about work done without a permit?

Not actually me, but someone in the neighborhood. Ft Lauderdale building code enforcement shows up and leaves a yellow sheet on the door about 'work done without a permit'. Forces seller to lower the price in hopes of a cash buyer as the house was part of an estate and no one can get permits to finish the work started years ago.

Have some of the info off the sheet they left, how do I go about finding out who made the complaint? I know if someone calls in that your grass is too tall or you put out your bulk pick up too early you can find out who called you on that.

Thanks for your help!