Nice group of ponies!!
Okay:
Bowtie - darker version $6-ish?
Blossom - CF I'm guessing? $4-8
Happy Tails Squeezer - Lovely pink hair! $6-10
TAF Fifi $7-10
Rainbow Flutterbye - she's all over right now, I've seen her as high as $20 and as low as $4 but in nice shape probably at least $10
Baby Quackers - seen her anywhere from $3 to $15, lol... maybe avg $6-9
Posey - her hair is a little faded, so, $4-6?
Princess Moonbeam - does she have a crown clip? Crown clips themselves can run like $50+, her probably $10-15
SS Posey - also hair faded, $4-8
TAF Up, Up and Away - hair faded, $6-10
Rainbow Tickle - again 2nd set Rainbows can be all over, especially in nice shape with little glitter loss, she could probably run over $10-15
SS Bouncy - depending on how much flock loss, of course $6-12
Princess Sparkle $12-20
Princess Primrose - she's more common, and with holes in her feet, eh... $4-6
Flutter Peach Blossom and Flutter Honeysuckle - most run between like $6-12, honeysuckle is a bit faded hair color wise.
Baby Tic Tac Toe - $6-12
Those are my estimates, sorry they are broad ranges, it really just depends on the buyer and the conditions and how badly someone wants them, lol - just like anything, of course! I hope I'm not too off on any of these.