What the law says
Wisconsin Statute § 704.085(1)(a) lets a landlord charge you their actual cost, up to $25, to pull a consumer credit report from a nationwide credit reporting agency. Read that carefully: it's a reimbursement with a ceiling, not a flat $25 fee. If the report cost them $12, that's what they may charge. They also have to tell you about the charge before they pull the report, and give you a copy of it.
The one extra charge the law allows
There's a second charge in the statute, and it applies to fewer people than you'd think: § 704.085(2) lets a landlord charge their actual cost, up to $25, for a background check — but only on an applicant who isn't a Wisconsin resident. Same conditions: notice before, and a copy after. If you live in Wisconsin, that one doesn't apply to you.
The "application fee" isn't really a thing here
If you're charged anything else — an "application fee", a "processing" charge, money to "hold" the unit — Wisconsin law doesn't care what it's called. Rule ATCP 134.02(3) defines an earnest money deposit as any payment, "however denominated or described", given to have your application considered; the only carve-out is the credit report charge. And earnest money has a rule attached: if your application is rejected, the full amount goes back to you by the end of the next business day. It isn't a fee they keep. It's your money.
You get a copy — that part isn't optional
Both charges come with the same string attached: the landlord has to notify you of the charge before requesting the report, and give you a copy of what comes back. If you paid for a report and never saw it, you're owed it. (Written permission is a different question — federal law requires signed authorization for employment screening, not for renting. A landlord can pull your report because you applied, which is what makes it lawful.)
If you're denied because of the report, they have to tell you
When a decision to deny you rests even partly on a consumer report, federal law (the FCRA) requires notice. That notice has to name the agency that supplied the report, and you have the right to a free copy from that agency and to dispute anything inaccurate. Errors on reports are more common than people expect, and they can be fixed.
If you already have a recent report, you don't pay again
This is the part almost nobody uses. Under § 704.085(1)(b), a landlord may not charge you for a credit report if — before they request one — you give them a report from a nationwide credit reporting agency that's less than 30 days old. Two conditions do the work: it has to be an actual report you hand over (saying you were screened last week isn't enough), and you have to provide it before they pull their own. Bring it up front, and that charge is off the table.
What to check on any application
Posting a unit on Fía is free for landlords. And whatever platform you apply through, these are the three things worth questioning: being charged more than the report cost them, a Wisconsin resident being charged for an out-of-state background check, or being charged after you already handed over a report less than 30 days old. And if you're rejected, any money that didn't go to the credit report has to come back to you.