Is a second job worth it for the money?

Life for a young adult in the 21st century is expensive.

On top of rent I've food, utility bills, transport costs and my gym membership to factor in for the month - and they're just the basics.

Before you know it, you end up with a whole bunch of extra costs because the vacuum cleaner exploded, or you locked yourself out and had to call a locksmith.

It's more crucial than ever to keep the money coming in - but it's also easier than ever to get a second income. Thanks to start-up companies such as Uber and AirTasker, you can become a part-time contractor in minutes and work your own hours whenever it suits.

But as lucrative as a second job may seem, there are a few hidden traps to watch for or you could end up completely wasting your time (and, in some cases, your money).

If you're looking for a second job, you have to make sure you're getting paid legitimately. Some small businesses can be pretty relaxed about their payroll system, so once you know the rate of pay make sure you check the Fair Work website to make sure you're getting the award wage for your age and the job description.

For example, Fairfax reported in March that hip food delivery services Foodora and Deliveroo were failing to pay their bike couriers - who are employed as contractors -the correct rates. And there are now so many cleaners on AirTasker in Sydney that the going rate to have a two-bedroom home cleaned is only about $50.

Try not to be exploited - if it's not worth it, give it up.

Some jobs can also involve mandatory extra costs. If you work for a clothing label, you may be required to wear full-priced items when working on the floor.

High-end labels can leave the employee largely out of pocket by the end of the month, so you have to consider whether these extra costs are worth it. Uber drivers also face the strain of extra costs.

Drivers in NSW were recently hit with fare cuts - a move that Uber believes will attract more users to the platform.

On top of petrol costs, Uber drivers are under the growing pressure of providing their passengers with freebies such as bottled water and packaged mints. It's become a much less profitable venture for drivers, so if you're applying for a job always take into account the costs involved for items such as qualifications, uniforms and the little extras.

A second job can also have tax consequences. With your main job, the first $18,200 of income is not taxable - it is the tax-free threshold. If you take up a second job make sure you don't claim the tax-free threshold from that employer.

It means you will be paying tax on every dollar you earn, but if you don't you might get slugged with a large tax bill.

"Your first job would attract the tax-free threshold, while the second and subsequent jobs would be taxed in line with the progressive tax tables supplied by the ATO," says Mark Chapman, from H&R Block.

"It causes taxpayers to be, in effect, undertaxed on their ordinary earnings, which can result in a tax bill at the end of the financial year."

Considering going "off the books" to dodge tax? That's also a big no-no, as it means you essentially waive your rights as an employee and will miss out on super and insurance. Bear in mind, too, that you have to declare your taxable income to the tax office, and if you don't and are caught, you could be penalised for tax evasion.

Sometimes a second job is just not worth it. You have to be careful that you're not wasting your time and wearing yourself out for virtually no pay-off. As always, do your research.

Get out the calculator and work out if the job you want to apply for is going to be worth the effort.

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