What floats your boat? Whether it’s cruising the Mediterranean on a yacht, houseboating on Lake Mead or sailing in New York harbor, you’re landlocked without a watercraft. But now a money-saving, peer-to-peer rental system means you don't have to miss the boat--or break the bank to buy your own. Boat sharing connects boat owners with wanna-be sailors; some companies or owners will add a captain or guide, if you need one. Here are five providers to consider when you're ready to "seas" the day.

Antlos

Antlos, “The Sharing Economy of the Seas,” offers affordable yachting. By eliminating the middlemen—charter agencies—that usually handle rentals, Antlos helps you save money. Want to see the British Virgin Islands or sail around Greece? Antlos may charge up to 33 percent less than a charter agency for a seven-day, all-inclusive yacht trip for six. Invite others to sign up, and you’ll earn travel credits to use on your trips. Manage your budget by opting for one of three types of accommodations: an entire boat, a private cabin, or a shared cabin.

GetMyBoat

Choose from powerboats, sailboats, fishing charters, houseboats, jet skis and more with GetMyBoat. This company lists some 58,000 boats in 169 countries, and a downloadable app for Android or iOS makes it easy to rent from anywhere. Want an airboat tour in Miami, a guided fishing trip in Anchorage, or a wildlife tour from San Diego? GetMyBoat can arrange a variety of excursions, including scuba diving from boats or paddle sports like kayaking.

Boatbound

With about 12,588 boats in more than 2100 cities, Boatbound.com has everything from 10-foot sailboats to 90-foot yachts. Just select a craft, pick your dates, and add a captain, if you need one. Boatbound, headquartered in Seattle, calls itself a “pier-to-peer” boat rental marketplace. Check out its online Destination Guides, which are sure to wet –we mean, whet—your appetite for great places to go.

WeAreOnABoat.com

Search online or book a watercraft from your mobile device. WeAreOnABoat matches renters and boaters so you can find boats in your area and book a ride. The app is socially oriented, so you'll also be able to read about your captain and meet other people. How much does a boat ride cost? WeAreOnABoat says your captain will suggest a “reward,” which might be some fuel for his or her boat or food, drinks, or other compensation.

Boatsetter

Boatsetter, which has been described as a kind of watery Uber, is an international boat rental marketplace. It works with U.S. Coast Guard certified captains (although you may opt to skipper your own craft, depending on which one you choose). Reserve a lobster boat and head out to catch your dinner, cruise a lazy river at sunset, or hop on a speedboat and take the family waterskiing. If you're a boat owner, you won't have to pay a fee to list on Boatsetter; you can also set your own prices.

Ahoy, Mate: What You Should Know Before You Leave the Dock

Safety comes first when you’re boat sharing. Try to meet the owner or agent and check out the watercraft before you sign an agreement to rent. If that’s not possible, read the online listing and rental contract thoroughly. Make sure you know how to operate the boat and use all its safety features before you shove off. A trial run, with the owner or agent onboard, can be a smart move.

If you’re new to boating, consider taking a safety course. GetMyBoat.com has information on boating lessons around the world. Boatbound links to online boating education and certification through BoaterExam.com. You can find more boating instruction links on the U.S. Coast Guard website.

When you rent a car, it’s wise to look it over and note any existing damage or problems, so the agency won’t think you’re responsible when you return it. The same is true for boat rentals. Use your smartphone to snap pictures, if needed, and discuss any concerns before you launch.

Find out whether the boat owner or rental agency offers insurance coverage. If not, you’ll need to get your own. Nobody wants to pay out of pocket for a damaged or totaled boat, or for medical expenses if someone gets hurt, so understand your rights and responsibilities. Boatbound links to a Peer-to-Peer Boat Rental Policy through GEICO Marine Insurance Company, offered by BoatUs.

Expect the boat owner to run a security and/or safety check on you before they’ll agree to rent; after all, boats can be expensive. You may be required to use a secure payment system, which helps protect all parties.

Ask about any extra fees for wakeboards or other items, so you won’t have any unpleasant surprises at the end of the rental period.

This sounds obvious, but if you’re new to boating, it’s easy to overlook: make sure you start your voyage with a full tank of gas (unless, of course, you’re renting an unpowered craft). Talk to the owner about what kind of fuel and/or additives may be needed, so you won't damage the engine. Also ask if you're supposed to re-fuel before you return the boat, or how much you'll be charged if the owner or agent does it for you.

Be aware that boat-sharing relies heavily on user and renter reviews. Owners want to know that potential renters are trustworthy and responsible, and renters want to make sure they're getting their money's worth. Finally, when you return your watercraft, remove any trash, wash down the deck, wipe out the seats and take care of any other housekeeping, so you will be welcomed back someday.