Yeah setting up a Garrison with treasure hunters and a T3 Inn can get you about 1k gold per character per day on average from missions alone and is abnormally safe since you are in your own little instanced haven. You can also extend that into the profession buildings + salvage yard to get a little more profit and toss up ore / herbs for a pittance profit. A secondary account with 4-6 characters should be sufficient for a Casual botter to not have to personally pay blizzard for another sub. Good news as well, Black Friday WoD (US) looks to be going on sale for 12$, Battlechest for $5, so brand new account + instant 90 for $17. Good time to roll out a secondary account!