Holley set up a payment schedule with Lohan before she agreed to represent her last week after the troubled actress fired her several months ago.
The pair also worked out how Lohan will pay her lawyer in the future, TMZ said.
The "Mean Girls" and "Freaky Friday" star began a court-ordered, 90-day stint at the Betty Ford Center rehabilitation clinic in California last week.
Lohan's once-bright career has been eclipsed in recent years by her battles with drug and alcohol addiction, motor-vehicle offenses and legal woes.
She was most recently seen in a guest role on Charlie Sheen's sitcom "Anger Management."