One solution I can think of in your case is :
- Start players with $0.
- Make them do some work for their starting capital.
- This work is avaliable forever.
- The returns from doing this work is far below all other activities.
The game is 100% player economy driven. That's the point of the entire game. It's why I'm making the sandbox game to start with. The players have control and build the world. So starting with $0 isn't really an option from what I can see as money has to get into the game somehow without any NPC involvement.
If someone buys 5 accounts, he "kind of" deserves having 5x the start gold, too.
It ruins the integrity of the game which can hurt the game in the long run. The game is also going to be on the low cost side so it wouldn't be a big deal for someone to get 50 accounts if they really wanted to have a ton of money.
I would never restrict on IP as I know the dangers there already.
Allthough wouldn't your name and address be tied to the cards anyway(Last time i checked my billing address is tied to all my physical and virtual creditcards), so it should still be possible to tie the purchases to the individual.
This is a good point. I could require a paypal account be used, which then paypal sort of takes care of the uniqueness on their end since you can't have one card linked to multiple paypal accounts. However I fear this might be limiting in the people that would play the game then if they don't have or don't want a paypal account. Can't we just use social security numbers already :) Come on world, we need to uniquely ID people for certain things :)