The first one looks like it has some Hotot (or something like that, can't remember the exact spelling) in it. I am thinking they are dwarf size, or there are dwarf Hotots. Maybe a Netherland Dwarf/Hotot cross?
The other one does look like a Rex, its harlequin colored. My favorite color! It may be a mini Rex?
Well, coming from an auction it is very possible they are mixed breeds, and it is hard to say without seeing them closer, knowing how much they weigh and approximately how old they are. However, my best guess, Florida White or if quite young, it could be a New Zealand White. If it is really small, it could be a Netherland Dwarf, but it's ears are way to big for a ND. The second looks like a Harlequin. It's fur does look sort of rex'ish, but its ears do not. I would guess it is pretty young, which would mean it's coat is still immature and that could be why it looks like that. OR it could be a mix.
I thought Dwarf Hotot (and yes there are two sizes, Hotot and dwarf hotot) when I first saw him too, then thought they black was just a shadow. Does he have black rings around his eyes? If so, it is a hotot, pronounced hoe tote.