People are finding all ways of moving around this earth. Electric cars charged by solar panels, an assortment of R.V.s, yachts, power boats, converted buses, biking, hiking and flying their own planes. There's nothing stopping you from inventing another way. I'm still waiting for my hoverboard - it's overdue. It'll probably be your budget that dictates how you get around.
Purchasing a car and driving in a foreign country has its challenges but often the effort is worth it to have your own bit of space and freedom for maneuverability, however, it comes at a cost. There's always a risk of buying someone else's problem. It's a case of buyer beware. Consider purchasing off fellow travellers on Facebook pages where they have numerous friends. They are unlikely to rip you off if you can make contact with again. It is certainly a case of 'buyer beware' and a level of trust in humans is required, but not all human nature is beneficial to others. Try and keep the costs low so the risk is lessened.
Find out the requirements for driving in a foreign country. Some islands we have visited required us to buy temporary driving licenses based on our existing licenses. Sometimes you will need to have an English translation done on your exisiting license and/or an international license. Road rules and driving conditions may differ greatly from your home country. Seek out Youtube videos about driving in the country where you are going. Make sure you drive on the correct side of the road.
If you decide to buy a camper van or R.V. find out about the restrictions for parking overnight. There are heavy fines for this in some countries. Also check out the price of caravan parks and ensure to include this when you work out your budget. Sometimes you might not drive long enough to charge the batteries and it may be necessary for you to plug into the main electrical grid. Buying a 'self contained' vehicle in New Zealand allows you to use the Freedom Camping sites. Ensure you download a free app from Rankers.co.nz to find out where these are located. Joining caravan clubs around the world can offer great discounts and cheap campgrounds.
Many countries, such as Colombia, Peru, Mexico, have great bus systems that enable you to reach the most remote villages. They provide an inexpensive means of getting around. In Jamaica they have a pretty good intercity bus system and for local travel you catch a 'route taxi' which is a taxi that acts like a bus. You pay a minimal fee for each section of the journey. This is a great way to meet the locals. Some islands through the South Pacific had no public transport system and the only option was to rely on the wonderful locals to offer you a lift. It was difficult to walk anywhere on these islands as everyone wanted to give you a ride. Caution of course needs to be extended in these circumstances. Flights are often cheaper than buses.
Flights are difficult to book from some South American countries because they are assume you are a local and you need to include some information that you probably won't have. On these occasions you need to use one of your preferred flight booking sites to assist you. There are definitely cheaper days throughout the week that are better to fly on than others. Each country will have its own pattern. Jump on a website and try and work out the best days through random searches or ask some locals.
You can sometimes find public ferries from place to place among the islands. Many of these have movie theatres and other entertainment. These are sometimes the only way you are able to move your vehicle around. Book well in advance for the best prices.