[Ren follows him with his eyes, not his feet. He's intrigued, yes, but not yet eager.]

Your old life in its entirety, for two years of this life?

[It seems a hefty price to Kylo. He's not certain why anyone would choose to enter into such a bargain... the power on offer would have to be immense.]

Sacrifice is always required for any power worth holding- though it sounds as if you intend to bend the rules.