Advice Needed winterization mess up

[S Cian]

Hey guys,

I just bought my first house back in January. Problem is that when the appraiser for the mortgage company went out to the house to do his thing he turned the water on to verify everything worked and no one re-winterized the property. Heat was shut off due to a past due amount of $35,000 so there was no heat, needless to say i had some broken pipes when i took possession as they weren't discovered on the walk through. It was a bank owned property and in an addendum on the purchase agreement it says that the listing agent is required to re-winterize after any inspection/appraisal. In contacting the listing agents broker and going back and forth with him he keeps saying theres nothing that can be done due to the property being sold and the bank closed the file. Today he said he'd give me $500 of the $1750 (billed by a professional who did the work, i sent the broker the invoice also) cost I incurred, claiming he cant do more do to it being a loss to him. My question to you guys is isnt he responsible for the whole amount since his agent screwed up and didnt re-winterize like she was susposed to? what should i do/can i do/ or what would you do if it was you? Thanks in advance