It costs us all of ourselves. This is the third stage of the cross. The desire for personal salvation is basically self-centered. Sanctification can also be selfish. It may be a drive for power and status, a kind of spiritual ego trip.
Intercession is different.
It goes out from ourselves toward others. It is a way of pouring the resurrection life of Christ into the world. The intercessor is a channel for the blessing of the ascended Lord. The right kind of intercession is infinitely powerful. One man, C.T. Studd, prayed the Gospel into Africa.