She said she heard glass breaking and looked outside to see a car in flames.
After ringing the Fire Service she went outside, just in time to see the car start rolling down the road.
"It's just rolled, missed the car that was blocking the road to stop the other cars coming up, and it's just gone straight through [the fence]."
Ms Purcell said it was "bloody scary".
"I was scared it was going to take someone out, that it was going to kill someone.
"I was really, really worried that it was going to cause more fires, that people were going to get injured. Anything could have happened, it's lucky there were no kids out."
Neighbours said the car narrowly missed a power transformer as it went through the fence and down the driveway.
It only missed the house because of a fence, which has been flattened.
Brandon Smith, 21, said he saw the car roll about 25m down the hill, over a speed bump, and through a fence.
He said the car was engulfed in flames.
It appears the car stopped just short of the house and there were no reports of anyone being injured.
One neighbour was seen trying to put the flames out with a garden hose while the car was still parked up the road in flames.
Jon Picard, 39, and Jason Shoebridge, 40, were inside watching TV when they heard muffled voices and then something that sounded like people "chopping up firewood".
Then glass started breaking.
Shoebridge said the sound of breaking glass got more and more repetitive, and when they went out on to the deck they saw a "burning mass" parked right outside their house.
"You heard the glass going because of the heat. It just killed the glass. She was pretty hot, man."
He said you couldn't make out what kind of car it was but that it looked like a four wheel drive.