It really depends on where you get them of course, but the marine figures don't vary in cost depending on the character. They can vary on how popular they are or how available they are. For instance, Vasquez with her smartgun is overpriced now on the second hand market because she was very popular and there aren't many left out there. There are recent two packs of Hicks and Hudson and they are a great starting point. I found one for like $32. A single marine can range from $15 to $25, depending on the seller, but yeah, Windrix and Frost usually cost less. Your best bet for the Hicks and Hudson is the relatively recent two pack. Vasquez in her BDU is recent and costs between $20 to $25. As for Vasquez with her smartgun? Good luck with that one, I just know she's hard to find and not cheap anymore.