foreclosure on houses

[jamazon]

I recently learned about this subject and do not understand why there is such a wide range of prices among houses. Some are listed at 5k, some at 15k, some at 200k (I tried attaching a search link to realtytrac.com but couldn't). Does this mean the house is only worth 5k if I buy it from the owner (which sounds ridiculous)? But then, what about those listed at 200k?

Thanks.

Thanks.