I have a 2nd account constantly gathering and selling on the AH with a decent amount of gold i'd like to give to my main account.. what's the safest way to transfer this money without raising suspicion?
The least suspicious is to buy an item from the other account via AH or a "legit" trade prior to a "conversation" between the two. One would normally say Guild Bank is safe, but it's so common nowadays that I'd be surprised if they weren't monitoring those.
The Guild bank is fairly safe as long as you don't drop it in and then just pull out on the other account, let it sit there and pull the gold/items out over time. As for the ah or trade you can't sell some random cheap item and buy it for 10k, you need to keep the value to price ratio within say 150%. Also if you do it enough they may catch on as that was a popular way to buy/sell gold in the past.