Hi!
Some animals like the Dachshund, Collie, Great Dane, and Cocker Spaniel definitely do go for a lot more money on eBay than the other G2 dogs. One of the main reasons for this is because of the ever-popular, fan-made Littlest Pet Shop series on YouTube by sophiegtv called "Popular"(it lives up to its name, for sure). Many of the main characters in the show are the same expensive ones you see on eBay; they are very sought-after by fans of the show. I've seen Dachshund #675, the main character of the show, go for $100 in the past. Surprisingly people do spend that much on them!
Try checking out the other LPS dog breeds- they are usually much cheaper!