Not true. It’s not that cheap. You need lawyer on retainer to file an unlawful detainer in Superior Court. You can’t file yourself.

If these are wannabe landlords, they probably don’t have an attorney. It’ll cost them about $3000 to get a lawyer on retainer. Plus they have to pay the filing fees.

http://www.courtinfo.ca.gov/selfhelp/other/landtenqna16.htm

Q. Do I need a lawyer to file or defend against an unlawful detainer lawsuit?
A. Almost everyone has the right to sue, or to defend him- or herself if sued, without hiring an attorney.

http://www.expressevictions.com/index.php

Uncontested eviction for $499
$150 – $400 attorney/contested fees

One week of recovered back-rent will pay for that.