The 95% mechanic only bites when the loan is bigger than the value. The general structure of a HECM is that an heir or the estate can satisfy the debt by paying the lesser of the balance or 95% of appraised value, so it's a floor for underwater houses. At 240 of value against 182 owed, there's equity, and the servicer just gets paid in full. Confirm the payoff, the per diem, and any deadline extension in writing with the servicer, because these are HUD insured loans and servicer discretion is narrow.
So the arithmetic that matters: your 145 to 155 is below the payoff. There's no deal at your number unless someone accepts less than what's owed, and on a HECM with equity that won't happen. The realistic clearing price is 182 plus accrued interest plus closing costs, call it 190 to 195 out the door, and then the estate wants something above that for the heirs. Against a 240 ARV needing 35 in work, that's a wholesale to a landlord at best, and probably nothing.
The payoff is also a moving target. Interest accrues monthly and servicers add inspection and property preservation charges while the house sits vacant, so the number you were quoted gets worse each month the family stalls.
On the unresponsive sibling: once a personal representative is appointed with letters, in most states the representative can sell estate real property without every heir signing, though what approval or notice the court requires varies by state and the estate's attorney is the one to answer that. Her consent to the distribution of money is a separate fight from the sale.
What you have not raised is the deadline. If the servicer's clock runs out before anyone opens a case, this goes to foreclosure, the heirs get nothing, and every hour you spent is gone. I'd want to see a filed case before I invested more calls.
