We could all use a little extra money, and a good side hustle is one way to get it. A side hustle could help you save enough for a down payment on a car or house, fund that vacation you’ve always wanted, boost your investment portfolio, help you pay down debt or whatever you need some spare cash for.

In an ideal world, you could put your money to work and enjoy a truly passive income, or your side hustle would be so lucrative that it could finally become your main gig. But even if you have to keep your day job, a side hustle can make you money in an area you’re passionate about.

A side hustle is something you do in addition to your main job, so the best ones don’t require a lot of time, give you flexibility in when you work and can help you earn a decent amount of cash. The ideas below include a mix of low or flexible time commitment and good value for the amount of effort likely needed.

Top side hustle ideas to help you earn more

1. Selling stuff in an online marketplace

People are familiar with third-party selling sites such as eBay, Etsy or Amazon, but you can take it upscale by selling on a site such as Poshmark, which offers new and used fashion items. An advantage of going higher end is that you may be able to earn more for the same amount of work.

You could sell items from others who don’t have the time or ability to do it themselves. But when you develop a deeper knowledge of the market, you could take it a step further by buying the top items directly from clients and then earning that profit margin yourself.

2. Become a virtual assistant

If you’re an Excel wizard or particularly good at organizing your online files, you can use these everyday skills to net you extra cash. Online platforms like Fiverr, Upwork and Outsourcely post administrative tasks needed by people throughout the world, and are often as simple as organizing one’s calendar or sorting through an Excel file.

Virtual assistants are paid for myriad reasons and can charge a rate they desire based on the amount of work. There’s no limit to what you can assist with online. Some utilize online platforms to illustrate children’s books for those who author them or even create family photo albums. Whatever you’re good at and have a knack for, it’s worth seeing if someone is seeking it out online.

3. Speaking engagements

Are you a master of motivation, a doyen of design or a ninja of cybersecurity? Take your expert skills and knowledge to an audience that’s willing to pay for your time. You’ll need to establish authority (through social media, blogs, books, videos or something else) and likely grow your audience first, but then you may be able to monetize that. Find a conference that’s willing to pay you to talk about what you love and then repeat the gig at new venues and for new audiences.

4. Tutoring

Everyone wants to ace the SAT or ACT or even just their next exam. Take your knowledge of the subject area and teach someone how to achieve success there. Nowadays you may even be able to do it from the safety and comfort of your own home through Zoom or other video conferencing software. If you have skills for standardized entrance exam tests for professional schools such as the GMAT or LSAT, you might be able to take things upmarket and turn an even greater profit on your time and skills.

5. Freelance writing

Freelance writing can be an attractive side hustle if you’re looking to fit in some work when you have time. It’s an even better setup if it’s in a specialized field with few competitors so that wages remain higher. Find a niche to write about, establish a reputation for turning in clean copy that needs few changes and then scale up as much as you want. You could turn that side hustle into writing about something you love or even a full-time position when you’re a known authority.

Is writing not your thing? Do the equivalent in media as a freelance video editor. Establish your credentials and then specialize in a subject area or two that you love.

6. Open a mobile business

Consider opening a mobile business for services that a user might not be able to travel to get. For example, consider a mobile service for replacing broken glass for windows in houses or cars. Schedule an appointment ahead of time and show up to fix the issue. You could focus on business outside of normal hours to establish a competitive edge and still keep your main gig.

Another option on the mobile theme could be a car detailing service. Bring your gear and get someone’s ride ready to roll in style.

7. Work as a ride-hail driver

Ride-hailing services have become popular in recent years, though COVID-19 certainly made it more challenging. But one benefit is the flexible hours. You may be able to work around your schedule, limiting your availability to nights or weekends, for example.

Many people opt for a major ride-hailing player such as Uber or Lyft, or you may also be able to set up with a regional player.

8. Move stuff

In a growing economy people are moving all the time, even if it’s only across town. Set yourself up as someone who can show up at any time and move that heavy item around the block or to the other side of town in your unused truck. You could expand into storing things for people while they’re in the process of moving from one residence to another.

9. Set up an online store

It’s never been easier to set up an online store through a service such as Shopify, and when you get things rolling, you really can make money while you sleep. It’s tough to beat that flexibility. Of course, the hard part is finding the products that consumers can’t live without and getting that community of people to your site.

But building an online store is the kind of thing you could work on in your spare time and build out incrementally as you learn the ropes.

10. Dog walking

Walking dogs sounds so old school, but it can offer a better payout than you might think. Plus, you can scale the business at least a little. Pet owners are likely to be wealthier than average (according to at least one study), and a busy pet owner in a city might not have time to walk their pooch. So, they may be willing to pay you to do the job regularly — and if you coordinate things right, you may be able to walk a few dogs at a time, doubling or tripling the money you make in the same period.

If pets aren’t your thing, you could take a turn as a house sitter. While some homeowners may pay in cash, others may be away for months and offer you a place to stay, helping you save on what is probably your biggest expense.

Bottom line

The best side hustles let you earn good money on your own terms, but it can take time to build up your side gig into something worthwhile. You’ll need to inform people of what you offer and show that you reliably deliver whatever you promise. From there you can see how big you can build your side hustle and whether it can become something even more lucrative.

Note: Bankrate’s Georgina Tzanetos contributed to an update of this story.