Seat of unusual charm and appearance (8)
I believe the answer is:
armchair
'seat' is the definition.
(armchair is a kind of seat)
'unusual charm and appearance' is the wordplay.
'unusual' indicates an anagram.
'and' is a charade indicator (letters next to each other).
'appearance' becomes 'air' (both can mean an impression or character).
'charm' anagrammed gives 'armch'.
'armch'+'air'='ARMCHAIR'
'of' acts as a link.
(Other definitions for armchair that I've seen before include "It's comfortable to sit in" , "Amateur" , "Roomy seat" , "Place for critic" , "Seat with side supports" .)