Has anyone ever refinished wood floors?

[XxLoFnKtAxX]

Me and the girlfriend and her family are considering refinishing her wood floors. We just took the carpet out not too long ago, and they were planning on just getting it done, but looking into it, it seems alot cheaper to put the work in. I found this video and am not sure if it is as easy as it seems.

http://youtube.com/watch?v=-xnNbipcZuo&feature=related

Apparently the machine at home depot is made for doing corners and stuff too.

If any one has done this, couple questions...

Hard or easy?

Is it a "If you sneeze, you'll F it up" situation?

When you put the polyurethane down, can you do one room and then do another room another day? Will the poly blend, or can you make it look good?

Tell me any input you have....

[gordy99]

when we moved in to my house, we took out all the old carpet and refinished the original wood floors. its not hard at all and with the poly, we just did it with a brush it looks awesome.

[XxLoFnKtAxX]

kill ur self or die trying easyforpp.

[Mill Creek]

My buddy Erik does it for a living, as far as sanding, all I know is keep the machine moving untill the drum has stopped, and move with the grain, not against it.
I could take pics of my living room floor to show what can happen if you F it up. Previous owners of my house tried doing it themselves, I have deep scars all over the place and the bad thing is, you can see where the actually sanded around a couple pieces of furniture. Sucks bad too, My G.G.Grandpa built this house in 1939, and now that I have it back in the family I have to fix everyone elses F ups.