Seems like whenever i come back to town, the money gained from what i sell is used to buy stimpaks, ammo etc.
so im gaining none but losing none.

Aside from that, I need 1000 caps to hire Jericho and im getting no where.

Any methods for makin fast cash??

Find the Outcasts at Fort Independance, and when ever you get extra power armor or energy weapons, bring them to Protector Casdin in front of Fort Independance, he will either give you stimpaks, 5.56 ammo, grenades, or radaway for your stuff. I suggest getting stimpaks, cuz if you get enough, you can sell your extras for a lot of caps. Thats usually how I get caps.

theres a glitch to get simple caps but it's complicated

It's all explained here And I can confirm it works with the patch