Two words of VERY important advice here: TRIP INSURANCE!
Find a good policy that covers all the various cancellation fees and reasons for cancellation, and factor that cost in to your plans and budget.
When I was younger and traveling solo I never paid much attention to the consequences of unforeseen circumstances. Now that I'm older (wiser?) and have responsibilities to a family of 5, I don't think I'd go anywhere uninsured if there were any uncertainties about the plan...