Be sure you're talking apples and apples. If you have painted hardwood or pine instead of oak, you may need to adjust. Just keep this in mind when you go at it. Also, you can search the WEB. Go to AltaVista WEB Search, and enter in: +refinish & +"hardwood floors" & -"north shore news" EXACTLY as I have bolded here, and press Search. (The '-north shore news' will eliminate 50 useless URLs.) You'll see the links I've listed and many more that include videos and books. If you price the job by a professional, you'll find that the money you save is well worth a video, a book, and/or renting the best equipment you can get. It's a very satisfying job. Read through the entire process before you begin to be sure you're capeable and comfortable with the task at hand.