Hey Nicole!
This is what I would do if I was going to get a cast photo multisigned
Robert Pattinson <-- Not the hardest signer, but the one who gets the most fanmail by far, so it would be good to get him out of the way first and not risk sending at a later date incase he stops signing or doesn't sign this generously
Kellan Lutz <-- Pretty good signer with a nice record autograph wise

I'd say pretty safe to send to him next
Jackson Rathbone <-- Same with him, personally I don't think it makes that much of a difference whether you send to him or Kellen first
Ashley Greene<-- Good signer
Nikki Reed <-- Great signer, she does sweet personalizing as well!
Peter Facinelli <-- I think he sends secretarials while he's filming, but by the time you get the 5 above he'll be long done

he's a pretty good signer as well
I'd wait until Taylor Lautner gets his next set of feedbacks, if he doesn't receive any by the time you get those first 6, I wouldn't risk sending to him and wait for an IP opportunity
Also don't forget to send another individual photo to each person as well

And I think you should explain in your letter that you're planning to get it multisigned so they don't do a big signature leaving no room for others
Good luck! {thumb2} Hope this helps!
Nich
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