The 7 habits of highly effective people. Stephen R. Covey
I like so much this book, it teaches so many things, one of those that I preach more is the 4 quadrant matrix for effective time management: An enlightening tool for people that live their lives solving crisis after crisis.
Another thing I learned from Australia is to use www.airbnb.com.au to check prices. If I got it correct in Australia is forbidden to have hidden charges, so, what you see is what you pay.