[Varyon]

Signature Gear is worth [1] per 50% of Starting Wealth worth of gear the character has. So, add up the worth of the target's gear (leaving anything they actually bought as Signature Gear out, as those points are already accounted for), divide by Starting Wealth, and multiply by 2 - add this number to the target's point total (you're taking whatever gear they had on them as Signature Gear). If you have enough points in your "morph budget" (the points you spent beyond the initial [100], plus whatever you lose by giving up your own stats) to meet this new total, you can turn into them; if you don't, you either fail or - if those additional points of Signature Gear made the difference - may be able to turn into them with less or no gear.

Optionally, you may want to apply an Enhancement to Morph to account for the fact that you create (temporary!) gear when you transform. Seeing as being able to turn into literally anything within your budget is only +50%, I wouldn't charge more than +20% (and note this applies to the initial [100], not to the additional points to increase your budget).