Actually, either option 2 or 3 will work. And they are about the same amount of work so there really isn't one I can recommend because it's easier.
I think I would create a new asset for the portion that was previously personal just in case I wanted to move back in so I wouldn't have to undo this again. But you seem to have a pretty good handle on this so do the one that works for you.
@jummus
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