He could simply be honest that he's expending a lot more effort on v2 to make it as awesome as he wants it to be. Charge the full price, but offer a refund or f

He could simply be honest that he's expending a lot more effort on v2 to make it as awesome as he wants it to be. Charge the full price, but offer a refund or full price rebate if you show that you bought v1.