Ghastly house I'd renovated (7)
I believe the answer is:
hideous
'ghastly' is the definition.
(thesaurus)
'house i'd renovated' is the wordplay.
'renovated' indicates anagramming the letters.
'house'+'id'='houseid'
'houseid' is an anagram of 'HIDEOUS'.
(Other definitions for hideous that I've seen before include "Unsightly" , "Repulsive" , "Extremely unpleasant" , "Horrible" , "Extremely ugly" .)