BoVinE said:
what do you all do for caps, I've always got less than 500 and can never get anything I need?
Beyond just scavenging as much as you can and finding traders (and when dealing with traders, repair broken items before selling them--often you'll get more for one decent weapon than two crappy ones), this is what I found:
1. Do quests and ask for payment (talk to everyone); most of them have a monetary reward in there somewhere
2. Find the ghoul who's making UltraJet and sell him Sugar Bombs for 15-30 caps a box. If you get the Blood Ties quest you will be told at some point three locations to search; the ghoul is in one of them (and that's in fact the place you'll want to explore closely anyway).
3. Solve the Blood Ties quest peaceably and sell Blood Packs.
4. Collect Pre-War books and sell them to the chick in the Arlington Library
5. Collect Brotherhood Holotags and sell them to the chick in the Citadel Archives
6. After helping Reilly's Rangers, agree to help them with their mapping project. This'll earn you LOADS, all for just wandering around. The hard part is just finishing the Reilly's Rangers quest so you can get to this point!
7. Sell Abraham Lincoln artifacts--there are at least three people who'll buy them from you, and it should be obvious when you encounter them.
8. Drink LOTS of Nuka Cola
I found early on it was hard to hold onto my caps for long but about midway through, it became a lot easier, especially after helping out Reilly.