EXP costs from Nicole's player

Here are some EXP costs from Nicole's player:

Attribute: Current rating x4
New Ability: 3
Ability: Current rating x2
New Secondary Ability: 2
Secondary Ability: Current rating x2
New Sphere: 10
Affinity Sphere: Current rating x7
Other Sphere: Current rating x8
Arete: Current Rating x8
New Background: 4
Background: Current rating x3
Willpower: Current rating x1
Merit/Flaw: Freebie cost x2

From 4th Core, excepting the Ability/Secondary which we have discussed. I have added two [and reasons why].

New Background: [Not listed in MtA Core. Checked VtM and WtA, not there either. Came up with number looking at other values].

Merit/Flaw: [Not listed anywhere. But needed for example, if Nicole/Serge wished to learn a foreign language. Value from a book on how to gain/lose them with XP]

ST's notes: Arete is earned through Seekings and not though exp. Backgrounds and new Merits and Flaws are earned mostly though roleplaying and not something that exp is spent on as per the house rules we play with.