Another question about adepts Options

[Traks]

I recently received MITS, and players immediately confiscated it for their own reading :)

So there is a question - if adepts buys some power, say deadly fists (S) and later wants an upgrade to deadly fists (D), should he pay the difference or full cost of powerpoints?

I also plan on giving a player who asked for ultimate powers (he said he would do anything, even betray a team for that) an initation. Which schools should be preferred, besides Aztlans with their blood magic? :) (Yes, he is asking to be screwed up, and I want team to get some pleasure in doing so). Also I plan on giving him "corrupt" template and giving him weak free spirit who will bond with him and will cause party members to be helpful (power like charm in AD&D, when you are willing to help the person in question. Willpower test of course.)

Any other ideas of helping to gain a power for a price are welcomed. Price will be unknown and steep :)