Oh and just so you know, Homura goes for about 13k B/B and 16k A/B on Amiami lately if you decide to go for the whole set.
Madoka's kind of hard to get these days. She goes for almost 20k A/B on amiami, I think 16k for B/B? I lucked out and got one from Navito World for $123 thanks to Meyneth who found some there that weren't listed on the NW web store (I contacted them directly and paid via paypal). Madoka is the only one of the set made by GSC (Stronger is making the rest of the set).
Mami's preorder phase is over already so you missed that, but there are sure to be a few preowned ones pop up.
I don't want the whole set, just Sayaka and Kyoko. Them being able to pose together is what sealed it.