Launching a side project or business can be lucrative, but it's also a lot of work. If you're looking for an easier way to make cash on the side, why not start with stuff you already have?

It's crazy but you probably have something lying around right now that someone else will rent and pay you for. Here's a list of items you might not have considered.

1. Rent your car

You've no doubt heard about AirBnb and VRBO as sites to use when you want to rent your home. But what about renting out your own car when you're not using it?

Instead of looking at your car parked in your driveway and earning zero dollars, a site called Turo lets you rent out your car, truck or van to people who are in need of a vehicle.

Sure, red flags go off immediately at the thought. Turo, however, offers several security measures. Drivers must first apply and be approved by Turo before they can rent a vehicle. Turo covers each vehicle with $1 million in liability insurance if anything goes wrong.

To help you determine if renting out your car is worth it, Turo's website offers a tool that estimates how much money you'll earn each year. For example, if you drive a car that's worth $18,000 and rent it out eight days per month, they say you can expect to earn an average of $3,142 each year.

Turo determines your car's rental price based on the current market value. Other factors, such as where you live and the time of year, are also considered in the overall listing price.

2. Rent RVs and boats

RVs and boats often sit and collect dust. In fact, most owners only use these toys around 10 percent of each year.

If you own an RV, a company called RVShare lets you rent your RVs to families or individuals who want to use them.

RVs are rented out by the day, and the price you can charge depends on your RV's size and local supply and demand. The average rates are anywhere from $100 to $300 per day. One woman from Waukesha, Wisconsin, shared on the site's testimonial page that she made $12,200 in 2015 by renting out her RV 10 times.

Listing your RV is simple. Just upload photos of your RV through the RVShare dashboard and you'll begin to receive requests from anyone who's interested. You can then review these requests and communicate directly with the renters through your account.

RVShare also screens drivers to make certain they're properly insured. Beyond that, a security deposit is made by the renters 48 hours prior to the rental date and is refunded to them once your RV has been returned in acceptable condition. Owners can also charge a fuel fee if the RV is returned without a full tank of gas, and a cleaning fee if it's returned covered in dirt, has stains, or is littered with trash.

A similar site called BoatBound lets you rent your boat to anyone who wants to get out on the water. Click here to see how easy it is to rent out your boat.

3. Rent your gear

Not everyone owns a big-ticket item like an RV or boat, but there are still ways to make extra money by renting out smaller pieces of equipment you might not have considered.

With the Go Green movement, cycling has become increasingly popular. In fact, a recent census survey found that 6 to 12 percent of people in some of the largest U.S. cities bike to work on a regular basis. These cities include Berkeley, California; Boulder, Colorado; Cambridge, Massachusetts; Portland, Oregon, and many others.

Spinlister is a site that lets you post your bike for rent when you're not using it. You can also rent out other sports gear such as surfboards, snowboards and skis.

At Spinlister, you set your rental price based on the hour, day or week. How much you charge depends on your location and your ride. Some bikes go for $3 per hour, while others go for $20 per hour or higher.

If your bike is lost, damaged or stolen, renters are responsible for the cost; however, Spinlister also guarantees protection up to $10,000. Surfboards are covered up to $2,000 and skis up to $1,000.

4. Deliver packages

If you're traveling somewhere and you don't mind delivering something on the way, you could sign up for a shipping network called Roadie.

Roadie connects people who need to ship items with drivers who are en route to the shipping destination, whether it's a neighborhood away, or across the country. Local jobs usually pay between $8 and $50, and long distance gigs with oversized items can pay up to $400.

Roadie shippers enter the item's photo and details into the app, along with pickup and drop off locations. Meanwhile, drivers can select which items to ship based on the places that are convenient for them.

Drivers are subject to background checks, driver's license verification and must also have valid insurance policies. You can make additional money by earning a Pet Lover Badge, which certifies you to transport pets for their owners.

5. Rent photography and video gear

Photography and video equipment are expensive, that's why renting this equipment is such an appealing option. If you have cameras, lights and other gear lying around, use a site called ShareGrid to rent them out for cash.

This site is primarily used by professional photographers who want to try out different types of cameras, and by individuals who are exploring new hobbies.

Top owners can potentially earn up to $1,000 per month, depending on their gear's value. The site provides a handy calculator. Just select your gear from a list of popular items, or enter in the estimated value. For example, a Canon 5D Mark III that is rented out at least five days per month can earn around $6,100 per year.

If renting out your car, RV or gear seems too risky or complicated, I recently posted an article detailing legitimate ways to make money online, including watching TV! Click here for over 30 ways you can earn money at home.