Hey, I'll try to answer all your questions.
It's never safe to even attach the bot to an account you 100% don't want to lose. (You can risk it, nobody can tell you, how high the risk is.)
You have to buy the game AND the gametime, yes. For each Account. Not really that cheap, but maybe you can get your hand on some cheaper gamekeys.
The best would be if you never transfer anything to your main, but IF you need to, take the route over a guildbank. (only a suggestion.)
And look here:
