How Much Help to Give PCs

[ClothedInVelvet]

Right now I'm DMing a solo adventure for a friend. I had him build a lvl 10, and he's basically on a treasure hunt. I wanted this to be an exercise in non-linear thinking (get out of the mindset of "I walk into the next room and kill everything there. Rinse and Repeat.")

So the rich man's daughter was kidnapped, and he hired the PC to find her. She really ran away to marry the tailor, but her father thinks she's been kidnapped and that seems to be the story the PC bought. The lead the PC took was that a powerful wizard cast a crazy protection spell on her and he might be able to sense her location through that bond somehow. So the PC went to find the wizard, but found out that he got power hungry and turned evil (Dread Necromancer/Pale Master). There's a paladin who's trying to kill him, but the paladin understands that, while they could probably kill the wizard, they're not going to get by the hundreds of HD of vampires.

So the PC has a couple options. He could leave the wizard alone entirely, and pursue the quest some other way (pay for a locate...). He could find some more powerful ally against the wizard. He could do what the wizard asks and just kill the paladin to get his help. But the player seems to be stuck, unsure of what to do.

So how much do I help him? I've rescued PCs when they did stupid things before, but I'm not sure how much is helpful and how much is just me taking over. What have you done in the past? What's worked? And what would you advise?

[Erloas]

Some of this depends a lot on the character. Killing a paladin to help an evil wizard isn't the sort of thing thats even really an "option" for any good character and even not that many good leaning neutral characters.

With lots of vampires to fight to get to the wizard, is hiring more adventurers to help really an option? Is it something they could do with 1 more character with them or are they going to need a couple more? Even with just the Paladin the player is only 50/50 on the action going in, adding in a few more characters is going to dilute the players influence to very little and you'll practically be playing the game by yourself.

How much of the real events have been hinted at to the player? Did he listen to the father for a few minutes and run off not having talked to anyone else or investigated anything himself? Expecting the player to "pay for a locate" sounds a lot like simply telling the player take 1000g off his character sheet and have some NPC tell him what to do next.
More hints need to be dropped that the evil wizard might not have anything to do with it.
The tailor would in theory also be missing, the daughter can't exactly run off with him if he didn't go anywhere. Is anyone looking for the tailor? Does anyone wonder why his shop has mysteriously closed for no good reason?(we'll assume he didn't put a sign on the door saying "ran off to get married, be back in 2 weeks")
If the player finds out someone else in town is missing they'll probably assume they are at least somewhat related. If, however, the story of the missing tailor doesn't at all match up with that of the missing daughter that be much more likely to investigate each. Especially if someone remembers seeing him with a young woman that at least vaguely looks like the daughter in question.

[ClothedInVelvet]

Right. I was hoping he wouldn't kill the Paladin. At least gets him off the linear track and makes him think about how he's going to act.

I'm not trying to necessarily get him combat action. For example, he knows of the wizard's arch rival, so one possible solution would be to enlist his help. (We're playing by email, and combat isn't something he needs to have fun, so I'm trying to create as good a RP experience as I can).

I would say the player knows a lot of what's going on, but not necessarily everything he should know. He knows that the wizard isn't involved, but he's struggling with leaving a powerful necromancer alone.
He also knows that the girl liked visiting the tailor, and that the tailor is acting strange lately. But the tailor is just now selling his shop and going to meet up with her, he hadn't left.
The player has done a lot of investigation around certain parts of the story (the wizard and his history) but very little about other parts (he hasn't even asked townspeople about the missing girl).

How would you give him subtle tips on where to go next? Or would you just wait until he figures something out?