Coleman's ex-girlfriend, Anna Gray, of Portland, Ore., filed a 2005 will on Friday claiming that Coleman had left her the majority of his estate and that he requested his extensive model train collection be given to hobby shops in California, People reports.
"Anna just wants to carry out Gary's wishes," Gray's attorney Randy Kester tells the magazine. "Her will is the most objective reflection of what Gary wanted. We're going to be in this case for the long haul."
According to Kestler, Gray was one of Coleman's business associates for about eight years and briefly lived with the late Diff'rent Strokes star in Utah.
Meanwhile, Coleman's ex-wife Shannon Price, 24, still claims she was the actor's common law wife and sole heir, according to what she contends is Coleman's handwritten will, which she says he wrote a week after they married in 2007.
Both women agree that the actor, who died May 28 at the age of 42, requested to be cremated.
While Coleman's remains have yet to be cremated, a Utah judge has appointed a third-party attorney to oversee the late actor's affairs.
An email to Gray's attorney was not immediately returned.