2.) Go to Andale (south central part of the map)
3.) Wait until around 1am and go into the Smith house while they're sleeping.
4.) Go upstairs into the kid's bedroom and use sandman on him (crouch and select him and and use the first option)
5.) Repeat step 4
You can increase the difficulty setting to gain more XP
If you have a good melee weapon or some ammo for the 10mm you should be able to make it easily. After arriving, you will start the quest "Tranquility Lane," when you finish, you'll gain tons of experience and be able to finish the story in less than 2 hours.
Then take one of the outfits then go farther into the cave you will see a dead end, but there is a scanner on the wall, go up to it and put on the raider outfit then click "activate scanner".
The wall will come down go inside there will be a shiny footlocker, in it will be the Trycor's rifle but you can choose the weapon type.
Also, there will be 500,000 caps and the trycor weapon will have infinite ammo and will be unbreakable.
There's also some power armour, and you can choose that as well and finally there's a note saying the code for vault 101.
Take the weapon and the armour last!