Belethor died for me too, his coffin is in the Hall of the Dead and his shop is always locked, if you go inside you find Ysolda who only tells you you're not supposed to be in there. I decided to respawn Belethor with the placeatme console command. Belethor went back to his shop but the selling dialog was gone. Now, Ysolda is the merchant inside the shop standing in front of the counter. And she still talks about owning an inn someday. Weird stuff. edit: Belethor's selling dialog came back after using the addfaction commands and sleeping. His shop still says locked but I have the key so I can still go in. Ysolda also has selling dialog. When the shop is closed she'll wait around in front of the shop and keep trying to enter. She has the same inventory and gold as Belethor. And they are both very fickle. Just at random times during the day they close the shop and will keep telling me to get out. Ugh... why can important NPCs even die.