In many locales, such as Eastern Europe and on islands, private rooms are your only real budget option.

Private rooms can range from an apartment to a room in someone's home. Hostel booking websites often list the most reputable private rooms -- choose these first. Airbnb and Home Away also list private room options.

When you arrive in a town, you may be assailed by elderly ladies offering a private room. I have found them to be safe options and usually the cheapest . Be aware, though, that they may be far from the center, which is why they are not listed on a hostel website. Have the lady show you on a map exactly where the room is located.

A note about couch surfing: I've never tried it. However, I've talked to people (in hostels) who have. Generally, the more adventurous, less-picky sort enjoy their couch surfing experience. Couch Surfing is the go-to website.