If you want to beat rapidly increasing car ownership costs, the Holden Barina Spark is your best bet, according to the RAC.
The motoring club's annual Vehicle Operating Costs survey shows that owning and using a car in WA has gone up by $20 a week in the past year.
And that's before the Federal Budget's increased fuel excise kicks in, should it be passed by the Senate.
Closer to home, the RAC says WA's on-road costs such as registration, licensing and compulsory third-party insurance costs are expected to rise by about 12 per cent in the next year.
The survey looks at factors such as a vehicle's drive-away price, fixed fees for items such as registration, running costs such as fuel and maintenance, and the estimated trade-in value of a five-year-old car.
The survey is based on vehicles privately owned over a five-year period, is insured with RAC and averages 15,000km on the road per year.
Among all these factors, Holden has emerged as the brand with the most affordable cars to own - including the cheapest of them all.
The Barina Spark light car costs an average of $111.76 a week to own. It benefits from having a low drive-away price, fuel economy, capped-price servicing and small tyres.
Holden's Commodore Evoke, Commodore Ute and Captiva 7 SUV all topped their segments.
In the small-car sector - the biggest-selling in Australia - the new Mazda3 has done its popularity no harm by costing $154.89 a week to run.
That makes it marginally cheaper than the Holden Cruze Equipe ($157.36) and the Ford Focus Ambiente ($157.37).
The Toyota HiLux is basically a lock to be WA's biggest-selling vehicle each year and was the third-cheapest 4x2 ute to own.
However, it failed to make the list in 4x4 guise, with the Volkswagen Amarok TD 420, Nissan Navara RX, Mazda BT-50 XT, Mitsubishi Triton GLX-R, Ford Ranger XL and Holden Colorado LTZ all cheaper.
At the opposite end of the spectrum, the monstrously proportioned Nissan Patrol came in as the most expensive car to own, costing a whopping $424.54 a week thanks largely to its high cost and thirsty petrol engine.
The RAC's Alex Forrest, who also writes the Idle Torque column in Saturday WestWHEELS, said it was important to consider the effects of depreciation when judging the cost of owning a car.
"Depreciation remains the least visible car expense, yet over a year it comprises almost 30 per cent of the overall cost of running a car," he said.
Among the biggest changes this year was the affordability of LPG cars, which took a hit thanks to the Federal Government withdrawing a $2000 rebate on LPG cars and planning to increase the LPG excise.
After arriving in March this year, the Mitsubishi Outlander PHEV is now Australia's cheapest electric vehicle to buy and own.
However - and this is possibly a chief reason why electric cars haven't caught on in Australia as yet - it still costs more to own per week than any other category winners apart from the Amarok.
- CHEAPEST CARS TO OWN IN WA *
Holden Barina Spark CD
$111.76 per week
Suzuki Swift GL
Volkswagen Jetta 118TSI
Holden Commodore Evoke
Ford EcoSport Ambiente
Mitsubishi Outlander ES
Holden Captiva 7 LT
Holden Utility V6
Volkswagen Amarok TDI 420
Mitsubishi Outlander PHEV