Pink Unicorn - G1 Year 4 Rainbow Pony - Pinwheel
Purple Unicorn - G1 NSS Buttons
Pink Pony - G3 Sunshine Blossom (from the Garden Stand)
White Unicorn- G3 Sweetie Belle
Yellow with Purple Hair- McDonalds Ponies
The rest are cute fakies.
mylittlewiki.org for more information :D
The mcD ponies are legit, but not worth 50 bucks. I've had loads of those over my years of collecting, and I used to send them as freebies to people in the US as they didn't get that set. I'm pretty sure we had them all over europe, so they're not at all rare here. They might fetch a higher price in the US, but not as much as 50$.
The white in Pinwheel's hair could be a faded pink streak, which *could* mean she could be a NC/spanish Pinwheel, as far as I can tell from pictures of NC pinwheel her hair looks to have a fading pink streak? Her eyeliner looks too light, however, to be a NC pony. My guess is it's a HK Pinwheel, but it'd be odd if that streak was faded as it's not the shade of pink that does fade easily.
It could tbh also just be the photo that washed it out. The lighting in it isn't the best.
:)