You can plug in the area you’d like to stay in, and the dates, and you will see a number of listings by actual owners putting their place up for rent, for a few days, or for months out of the year. If you opt to use Airbnb, be sure to read the descriptions well, since some places will rent you the whole house or apartment, some places are renting out a room in an occupied house. Also, the house may have certain pets you should be aware of, if you are allergic in any way. Some listings are for RVs to explore the area or a National Park! How about a Treehouse for rent in the middle of a forest? Reading as many reviews as possible by other users is most important as well, as they will give you an idea of what kind of stay you will have, how clean the place is, how involved the owners will be during your stay and how much noise to expect from your neighbors. The NY Times recently had an article written by Stuart Miller about his own experience with his family on a road trip in the South of the United States, staying at different homes through Airbnb.
If you do your homework and spend some time during your search, you will be surprised what kind of properties are available at an affordable price! Maybe a beach-front property with all your necessary beach gear plus BBQ grill for under $100 a night!
Happy traveling and happy searching!