I am purchasing a very well-established website that was in the past one of the leading websites in its field. It was created in the late nineties and was listed extremely well in Google for many years, until very recently when it was hit very badly by the Panda or Penguin updates (or both). Google clearly found some very serious problems with this site as it seemed to almost disappear from the listings. It has gone from around 250,000 in Alexa to around 3,500,000. The extreme drop in listings was probably also something to do with the fact that the owner seems to have lost interest and the site itself has been down for a couple of months. Before the site went down it was still above 1,000,000. I have decided to purchase this site because of its longevity and fairly good brand name and I am willing to be patient whilst I try to rebuild it's reputation with Google.
How would I go about this? Is it possible to report the change of ownership to Google? Will they be able to wipe the penalties if I show to be running the site properly? How long does it take to restore a site like this so it's Google reputation is repaired?