Possible Clues:

• Windows specialist less willing to work below $1,000
• Sounds as if the pain of his work makes him work less at last
• Tradesman who's good, but not so keen on working
• Craftsman less inclined to work after midnight
• Craftsman less inclined to work hard after good start
• Gee, one is even less inclined to work on the see-through! (7)
• Window repairer
• Tradesman who may give you a pain, thinking aloud
• Window mender
• He could prosper, or not, according to his lights