Who said that you have to travel with a companion to save money? In recent years, solo travel has been on the rise, especially with women. A 2014 study by Booking.com found that the increase in solo travel is largely due to travelers' ability to stay in touch with friends and family, thanks to multiple social media platforms. While modern technology has made it easier than ever to keep loved ones updated, it hasn't solved one of the biggest issues independent travelers must face: how to budget. Without someone to split the tab with, how can you ensure you have the same enriching experiences? Here are three money-saving tips every solo traveler should know.See: How to Travel SoloHome exchange sites like Couchsurfing and Airbnb have revolutionized the sharing economy. Both services connect travelers in need of a place to stay with locals willing to provide the space. The two sites operate differently, each with its own benefits.Couchsurfing has been around since 2004 and it boasts a well-established community of travelers worldwide. More than 9 million people use this service in more than 100,000 cities across the globe. Couchsurfing's biggest draw is that it's entirely free. Just sign up online, complete your profile and search for locals in the destination you're planning to visit. Once you find a local you feel is compatible, you can exchange messages directly on the website and arrange to sleep at his or her house for free. Your bed will likely be a couch, but it can also be floor space, or even a private room. This service is the ultimate way for budget travelers and backpackers to save money, while reaping the benefits of interacting with locals on a more personal level.Airbnb debuted in 2008 and has exploded in popularity over the past two years. As of September 2014, the company touts more than 800,000 listings in 34,000 cities and 190 countries around the world. The main difference between Airbnb and Couchsurfing is that with Airbnb you must pay for your accommodations. But keep in mind: Your Airbnb bill will likely be much lower than what you would fork over for a hotel room. To get started with the site, simply register online, fill out your profile and start browsing accommodations around the world, which range from apartments to castles. There is an excellent rating system for each host, where you can read detailed reviews from other users' experiences. Once you find a place that fits your needs, you can direct message the owner and pay for the property through the website's secure system. See: Ways to Avoid Apartment Rental ScamsIt can be difficult to resist buying every commemorative trinket you see when you're on the road. As travelers, we tend to find things more valuable when they're from a foreign destination because they appear to be rare and unique.But one of the easiest ways you can save money as a solo traveler is to cut back on your souvenir expenses. Instead of purchasing small keepsakes, save mementos from your journey: collect photos, posters, city maps, museum tickets or flight boarding passes. And instead of exchanging all of your foreign currency, hold on to a few bills or coins. Thankfully, most big cities have some form of reliable public transportation. Some systems are more efficient than others — Singapore, London, Paris and Seoul, South Korea are ranked among the best in the world, according to a 2013 CNNTravel reader poll. However, you should refrain from using public transportation unless it's absolutely necessary. Public transportation costs can add up quickly and can put a major dent in your overall budget.Try renting a bike instead. With two wheels, you'll experience a different perspective and might even discover some hidden gems. Grab a city map and create your own tour. You'll be surprised to find that you're covering more ground than you would if you were taking public transportation — and you're doing it for only a fraction of the cost. Walking around a city is a bit more time consuming, but it's another cost-effective alternative. When you're leisurely meandering, you'll begin to notice all of the little quirky things that happen at any given moment in a city. You'll also be able to people-watch much easier, and consequently feel more immersed in the culture.See: Best Places to Explore SoloAbout the author: As a recent University of Wisconsin-Madison graduate, Drew Goldberg has visited more than 40 countries since 2012. Drew is currently teaching English in South Korea, blogging about food, culture and nightlife at The Hungry Partier. You can follow his adventures on Twitter, Facebook and Google+.