So I''ve been playing for awhile. And I have this issue in Whiterun with un-owned shop now just as you enter.
WarMaidens is now always showing as locked, When I have locked pick and gone inside the shop is empty..
But the 2 npc still stand outside and I am still able to sell items to female NPC outside.. but The guy inside the shop is gone.

Where did he go?

My Chart is lvl 49 currently.. Yeah I think in past I have messed around. but I am 100% I did not kill
the shop owner. I do remember waiting outside the shop till next morning and he never returned..

I just kept checking back but in my game he never returned..

I don't even know where he went or if he's dead? Maybe he wander outside and got caught in blast from one the dragons..
I do not know.. Is there way to bring him back in console please and or way to fix this?

Thank you

I had this happen and it eventually worked itself out in a few levels. I think he's stuck in the inn.

He's been missing since I was lvl 20 something. I am now lvl 49.. Its really started to concern me more.. I should have
posted a lot sooner..But I figured it fix it self. but Never did. I really need fix for this please..

I have gone inside-picked the lock and searched He is not there..

I am still having a issue with this, please if anybody could give answer. I would really like to know how find this NPC and/or spawn him back please in my game

Wait outside for the door to unlock, or wait inside the store and he'll appear. It takes about 3 or 4 minutes in real time for me, and it can happen at any time during the day.

There are a couple of bugs related to Warmaidens, and that's one. The other one is that smith outside is supposed to have a separate inventory from the guy inside, but if you talk to him first in any given 48 hour cycle, she loses her unique inventory and adopts his.

I have tried waitiing outside with no luck. But I will go try waiting inside.. Thanks for info, And the door never seems to be unlocked,

You don't really need Warmaiden's - you can sell most stuff to Belethor, and anything left if he runs out of gold, you can sell to Eorlund. Or fast travel to Riverwood and sell to Lucan. Or all three if you need to.

This happened to me when I was doing the companions questline. You are sent to go get witch heads and when you come back the comapnion hall was attacked. If you notice outside the hall the maiden smith is standing outside at the bottom of the steps from the hall. If your companions quest is bugged then this is why the shop always remains locked.