Staying neutral at high levels in Fallout 3
This problem has different solutions depending on how you want to play.
If you're just looking for the achievement, one solution to your problem is to do whatever missions you want, choosing the side of good, until you get relatively close to your level point. Then go into a town and steal (for minor karmic reduction) or lay waste to entire towns (for major karmic reduction). You can quickly lower your karma this way. Then, once you're neutral, go kill some random creatures until you level.
(If you're looking to steal, a good place to do it is at Dukov's place… he's got stuff everywhere.)
The "nice" thing about this system is that if you stay on the path of "good" the whole time, you can do this at each achievement point: be bad until you get to the right karmic level, level up, get your achievement, and then restore a save to get back to your good self. You can quickly get "good", "neutral", and "evil" achievements for all levels on one playthrough this way.
(I did this, because I don't really enjoy long-term playing as an evil character… but I do like my achievements!)
You could also do this as an evil or neutral character, but it's much easier to quickly drop from "good" down to your new goal, than to work your way up.
If you find that you're close to leveling, and you're at the right karmic level, and don't want to take a chance on changing your Karma by doing a story-type adventure, you can always go wandering looking for random bad people to take out. Going near the Washington Mall can get you some XP fairly quickly, and you can go inside the capitol building and clear out large areas without picking up any Karma, positive or negative.
As long as you don't complete a quest with significant positive/negative karma ramifications, you should be able to balance your karma with some simpler, non-quest activities:
Positive balance:
- giving caps to the church in Megaton
- giving purified water to the beggar outside of Megaton
- for a serious positive balancer - you can donate scrap metal to Walter after completing the unmarked water treatment pipe leaks quest in Megaton.
Negative balance:
- stealing :) Any item described in red will result in negative karma if taken. However, if you steal something in front of another person, they may begin treating you as hostile which can lead to option (2)...
- killing a townsperson. (this can be tricky as killing one usually leads to a mob assault, which usually leads to the whole town being wiped out)
Once your experience starts getting close - visit Megaton or any other settlement and try to balance yourself out.
You guys are going of being neutral too stratiegically. My main character is neutral and the best way to be neutral IS doing the quests that alter karma. Being neutral doesn't mean gain experience as carefully as possible. It means playing the game YOUR way, making the choices YOU want. Sure you will hit the good and evil marks sometimes. But the beauty is that you can do more quests to balance it out! But if you need to know there are some things that give you neutral karma off the bat.(Gaining neutral Karama results in a vault-boy with a beard to appear. Rather than one with a halo or horns.)
During Growing Up Fast! When Amata is being harassed by Butch.Simply run up and punch Butch. This grants neutral karma. While its relitavely useless so early in the game.
During Trainquilaty Lane do all of the girls task except the last one, go activate the failsafe. And youll get neutral karma.