Application fee legalities?

[Brandon Schlichter]

Trying to find out what the law(s) are regarding application fees?

So far we've been doing $20/adult with a max of $40 for a application fee for bagkround checks and whatnot. Usually only someone who was willing to pony up the cash seriously would do it, we'd check them and all was well. However i've picked up several nicer properties and have 6-8 parties per property willing to pay application fees to try and get a chance at the property. I don't know how to handle it, because I don't want to run into legal problems with taking and not refunding fees after we've run the check on them.