Say you approach a Jarl or Innkeeper looking for work, how often does that refresh or is it good for so many times?

Btw is there a glitch with the Jarl in Winterhold ? I've done the same quest for him twice now (the helm quest)...and the kill the dragon at last tongue overlook i've gotten twice as well...hmmm..

You go to Yngol barrow once to get the Helm of Yngol, and once to get Helm of Winterhold. So it's normal to go there twice.

Radiant quests are random and they do repeat if you do it enough times. So If you killed the dragon at the Lost Tongue Overlook over 10 days ago game time, you have a chance of being sent there again.

Um....I've never checked, but I would assume you might need to rotate holds when it comes to those inn/jarl bounties.