Firefighters responded to the blaze, near E. Shelton Springs Road and E. Blevins Road N., at about 9:15 a.m. Monday after receiving a report of a house fire.
"Massive flames. I showed up here and flames were way up there -- maybe as high as the trees almost," said property owner Darlene Pennock.
The home, RV and trailer all were a total loss, but fire crews prevented the flames from spreading to other nearby homes, according to KMAS Radio.
No one was injured in the fire, but power was knocked out in the local neighborhood.
Mason County investigators say an electrical problem was likely to blame for the fire.