Vanessa, I was once involved with a similar situation over in that area. The owner was emotionally invested in the property and didn't want to consider the buyer or investor side of purchasing a tear down. In that situation, where the home was unsalvageable, the comps need to be run as land-only. Which, in their case, were about $100k lower than what she had hoped. It's kind of like trying to sell a car with great wheels. But the rest of the car is damaged beyond repair. At that point all you're really selling is a great set of wheels and some scrap metal.
I tried running the property through the investment channel. But nobody wanted the property at the price she was asking. The only advice I could give her was to let me list it on MLS and seek a retail customer. But she claimed she had already signed an exclusive sell agreement with a realtor friend. At that point I needed to walk away.
I would try convincing your mom to list the property on MLS. There are some cheap listing services like Zillow. Even if she only pays the buyers side of agent fees, it's still better than being stuck with the property when she wants to move on.
Good luck.