This is only my own limited experience , there are others on this forum who know alot more then me . I always go with the Dwanguard side. If while trying to lvl up my toon , I ignore the Dawnguard Quest line , The Vampires kill , vendors , and blacksmith's . If I jump right in and do the Quest line this almost never happens . Also fast traveling only during daylight hrs , and say you want to go to Riften I always pick spot outside , that location to travel to. Hope some of this might help you , cause I know how frustrating it is having key in NPC gone , and yer standing there wanting to sell . I really did'nt quite understand your post , but only trying to help here maybe a little........ Cheers Mate
