site and the gardens are beautiful, thank you for posting it. I looked in the history section of the site and it said Jane did stay there but it seems in a smaller house on the estate and not the main one--here is what it says with reference to JA:

History of Goodnestone

Sir Brook Bridges and Fanny Fowler's daughter, Elizabeth, married Edward Austen, brother of the famous author Jane Austen. Edward and his young wife spent their early married life in a house on the Goodnestone estate before moving to nearby Godmersham. Elizabeth was a favourite relative for Jane Austen (her daughter Fanny later became one of Jane's favourite correspondents) and Jane was a regular guest at Goodnestone during their years there. It is significant that she began writing her first novel, Pride and Prejudice, immediately after staying at Goodnestone in 1796.