Spoke to Larry. It wasn't totally destroyed. The front section when people walk in, containing rare accordions and some of his own, including parts like reeds and displays cases are all gone. I think the back sustained less damage.
According to the fire marshal, it was a faulty electrical outlet that went bad, starting the whole fire. According to Larry, he's going to rebuild. At his age, it's quite an investment, but i'm sure his grandson and family will be helping out.
The good thing about all the good Larry has done for people over the years, is it sounds like it is being returned to him in the manner of helping hands. Appears some priceless things gone, but not a total loss and no one hurt.