Any darker blue or purple pony must be watched closely and checked daily as they can start to get too bleached. I tend to cover their whole bodies except for targeted spots and then check under the tape each day to make sure they're not lightening past the point of the rest of the body. I noticed this with TAF Love Melody while fading some marker spots. If you're doing a whole-body fade to take care of dinginess for blue/purple ponies, check them religiously and keep in mind they need much less time to sunfade because darker colors absorb sunlight while lighters colors reflect it.

White ponies should be watched closely too but I have had fantastic success with Sundance, Quackers and Baby Starbow. It seems that most white ponies should be tested because sunburning potential depends on the batch... With the exception of Cherry Treats, who will always turn brown because of the way the fragrance infused in her plastic reacts to sunlight.

Yellow ponies on the other hand seem very resilient in sunlight, with marks fading but the body color staying bright. So I don't have to be quite as particular about covering them.

I have not sunfaded any green or pink ponies yet so unfortunately I can't give any tips for those body colors. I suspect they are a bit like the blue and purple ponies but to a lesser extent. 

For covering symbols I prefer to use cheap acrylic paint. It's the most precise option and especially for TAF ponies the easiest. To remove, just scrub with a cotton ball soaked in rubbing alcohol.

For eyes, I rip off tiny bits of blue painter's tape and slowly cover each area. The tape tends to peel up so at the end of the day I make a point to check it. I no longer use this tape on symbols because it can leave a sticky residue behind that is impossible to get off.

For hair I fold it into tinfoil and tape along the very base of the mane with painter's tape, being careful to avoid light leaks or getting more than the edge of the tape on the neck.

Placing her on a mirror will help get at those angles that aren't facing the sun if you haven't already done so I also find I have to rotate my ponies quite a bit to make sure every inch gets a good amount of sun exposure.

I probably would have put him down, but I can understand why you wouldn't have the stomach or supplies to do that. I have encountered various injured animals that were too far gone to survive (usually hit by cars) and usually feel the best thing I can do is just end things for them quickly.

I rescued a baby goose once who was rejected by its mother because it had a deformed leg, and intended to bring it to a wildlife center but it died overnight from the stress of the whole experience. So sometimes even when you make the effort for an animal that isn't badly injured it will still not make it anyway. Being around humans can be traumatic.

It sucks to have to see this stuff, but at least you did your best to comfort the little guy and gave him a little love in his last hours. It's more than a lot of people would do.

Giving this a resurrection bump :S

Thanks everyone! I have started a couple of auctions, I won't be able to do the bulk of them until next week. I'm glad I asked though!

Ahhh those bonnets! I cannot take it, so cuute! I will have to look into buying pony clothes from you 

There are a lot of MN collectors, make sure you look into the MN pony meet this year

Some of the limited release playset ponies and later Euro ponies are HTF for US collectors. The Mansion pony and her baby, for example, had a small release.