People wanting only the bare minimum should ensure the oil and oil filter are checked and the engine coolant as well, he says.
Topping up the brake fluid and checking the brake pads are also important.
"They are things that can't necessarily be seen from outside or underneath the car, so when you have a Warrant of Fitness done all they can do is check that the brakes are working but they can't tell if the brake pads are nearly worn out," Bayliss says.
What will it cost?
All garages should have a standard service fee. If you're unsure, ask.
Motor Trade Association mediation adviser Allan Barr recommends people ask as many questions as possible before a service.
"It comes down to communication first of all," he says.
"A lot of times, the repairers say, 'We know what's wrong with this and we'll fix it up for you'."
Disagreements over price often arise when the mechanic and customer have failed to agree on a cost prior to service, he says.
The most basic vehicle maintenance service offered by AA Auto Service and Repair outlets costs $159 for non-members. This jumps to $359 for its most "Euro Platinum" comprehensive service.
Barr says while most garages offer similar prices, any repairs will cost extra to the listed work.
How do I keep tabs on extra costs?
The service fee listed or quoted by garages is basically how much it costs to have a mechanic look over a vehicle and identify what's wrong.
Simple things, like changing the oil, can also be included, Bayliss says.
Both he and Barr say the owner must be consulted before any further repairs adding to the service cost are undertaken.
Before approving the work, customers should ask how much it will cost and what this price includes, Barr says.
For example, a repairer may quote a price of $200 - but this might only include the cost of a part.
Labour, which costs on average $90 an hour, is extra.
People may therefore be billed another $300 for three to four hours labour on top of the original price, Barr says.
Requesting a quote detailing the cost of a job will minimise the chances of any nasty billing surprises.
For more expensive repairs, people should ask for an estimate because it formally sets out the cost of a job, he says.
What happens if they do work without my permission?
According to the Consumer Guarantees Act, motorists are not liable to pay for any unauthorised work performed on cars - as long as they have been clear about the service's limits.
For example, if a driver drops their vehicle at a garage and says "fix it", they will be required to pay the full amount for any work performed, the Citizens Advice Bureau advises.
However, if repairs are performed without permission from the vehicle owner, and an agreement on cost with the garage is not reached, the case can be referred to the Disputes Tribunal, Barr says.
