First contact your agent's broker and explain your situation and how rudely you were treated.
Second contact your attorney, they are the one who will get this resolved. You may have a claim against the Preservation & Maintenance company for botching the job if the seller doesn't make good on repairs.
I'm really sorry this has happened to you...my advice is to go to the broker of the real estate company and explain the situation - that may be your best bet in getting the issue resolved.
I've seen photos of what can happen when pipes burst, not fun. Sorry it happened to you - to those reading this, properly winterizing a home is essential, and be sure that the water and power are on for your inspection and walk through.
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