Is there any way to make a NPC non-hostile through the console commands?

I was doing the hunting party quest near Falkreath where you go meet Valdr outside Moss Mother Cave. I heal him with a potion and tell him I'll go in to clear the cave. When I emerge he is hostile.

I tried running away and waiting for awhile and hoping he would calm down but he had moved to the inn in Falkreath and wouldn't talk to me. I also had a 40g bounty in Falkreath which I'm not sure how I acquired. Possibly a console command to remove bounty may help?

http://www.uesp.net/wiki/Skyrim:Console.
There's a resetAI command that may work. There's also a paycrimegold command that lets you pay off your bounty in a given hold.

Hope that helps.

If you're a vampire, that might cause that sort of issue - if you went over to stage four while doing the quest, he would be hostile when you returned to him. I don't think it would be the bounty - if it was, he would have been hostile to begin with.

Did you try casting calm on him? That might work.