These are some manners to get money:
- Warmonger; do the missions for your faction (if you are in one). They will pay $200 per mission. Think about the weapons you'll need and plan carefully how you will attack.
- Maniac in a mask: Get the sky mask (they are found in convenience stores), put it on and make war on society. Apart from looting and hide your identity, you can torture leaders. What did you think the duct tape and car battery were for?
- Commodities Trader: Resources trading is very lucrative. Even more if you have the Storage skill. Buy at $20 and sell at $90. Taking over a warehouse will halve your expense, increasing your profits further.
- Scanverger: Just loot buildings, or wait for zombies to kill SWAT/Rebels to have thier guns. Remember, if they are killed violently they won't drop a gun. Sentry guns and teslas can be found in the compound.