is any of his house preserved?
Yes, his Baltimore home is now the Edgar Allan Poe House and Museum.
Edgar Allan Poe
3 West Range is the dorm room that Poe is believed to have used while studying at the University of Virginia in 1826; it is preserved and available for visits. Its upkeep is now overseen by a group of students and staff known as the Raven Society.

The earliest surviving home in which Poe lived is in Baltimore, preserved as the Edgar Allan Poe House and Museum. 
who was rufus wilmot griswold? An anthologist, editor, poet, and critic. who was poe? A writer, editor, poet, and literary critic. was there anything particular about the relationship between the two men? Though in the beginning both enjoyed a cordial relationship with Griswold publishing Poe's poems and the latter writing a favourable critical review for the former, later it was strained due to various factors. did the second person have any other interests apart from literature? Yes, in cryptography. does he find any mention in first person's memoir? Yes, he is depicted as a depraved ,drunken, drug-addicted madman there.
wiki:1544933
Edgar Allan Poe [SEP] Preserved homes, landmarks, and museums
Poe's final home is preserved as the Edgar Allan Poe Cottage in the Bronx. In Boston, a commemorative plaque on Boylston Street is several blocks away from the actual location of Poe's birth. The house which was his birthplace at 62 Carver Street no longer exists; also, the street has since been renamed "Charles Street South". A "square" at the intersection of Broadway, Fayette, and Carver Streets had once been named in his honor, but it disappeared when the streets were rearranged. In 2009, the intersection of Charles and Boylston Streets (two blocks north of his birthplace) was designated "Edgar Allan Poe Square".