Card Worth

[parkesaurus]

Yeaaaah, so I haven't looked at my pokemon cards in about ten years; I don't even know why it occurred to me to wonder if they might be worth selling all of a sudden.

I googled and found this place and, well, here I am, hoping anyone might be able to give me an idea of what I'm working with.

Are 'promo' cards worth anything?
I have:
Pikachu, Sabrina's Abra, 2 different versions of Mewtwo

Shiny:
Nidoqueen, Muk, Mewtwo, Electrode, Hitmonlee, Vaporeon, Kangaskhan

A first edition shiny Aerodactyl
A shiny promo Dark Persion, has '17' instead of the rarity symbol

First Editions:
Golbat, Tentacool, Horsea, Shellder, promo Ekans, Kabuto, Paras

I also have a Squirtle and Wartortle that have what appears to be a pokeball over the number 2. I have no idea what this means.
And Magnemite, Metapod, Dragonair, Starmie, Persian also like this.

I have 3 different versions of Psyduck - one is normal and 1st Edition, another is in a foreign language, and the last has an R on it?
Also with an R:
Mankey (looks cartoonish), Ekans (not first edition), Charmander (also cartoony)

I'm guessing the trainer and energy cards are essentially worthless?

I'll be super grateful to anyone who bothers to reply to this! I just went through all of my old cards in those silly clear card-collecting binder pages as this seemed the best place to ask that I could find.
Thanks!!

[Odd-ish]

Originally Posted by parkesaurus

Yeaaaah, so I haven't looked at my pokemon cards in about ten years; I don't even know why it occurred to me to wonder if they might be worth selling all of a sudden.

I googled and found this place and, well, here I am, hoping anyone might be able to give me an idea of what I'm working with.

Are 'promo' cards worth anything?
I have:
Pikachu, Sabrina's Abra, 2 different versions of Mewtwo
the promo pikachu could be worth something, depends on a few other things, but the others are meh.
Shiny: holo
Nidoqueen, Muk, Mewtwo, Electrode, Hitmonlee, Vaporeon, Kangaskhan
bout 5 dollars each if in mint condition
A first edition shiny Aerodactyl
A shiny promo Dark Persion, has '17' instead of the rarity symbol

First Editions:
Golbat, Tentacool, Horsea, Shellder, promo Ekans, Kabuto, Paras

I also have a Squirtle and Wartortle that have what appears to be a pokeball over the number 2. I have no idea what this means.
And Magnemite, Metapod, Dragonair, Starmie, Persian also like this.
these are POP promos. prolly not worth much
I have 3 different versions of Psyduck - one is normal and 1st Edition, another is in a foreign language, and the last has an R on it?
Also with an R:
Mankey (looks cartoonish), Ekans (not first edition), Charmander (also cartoony)
the "R" means it came from the set TEAM ROCKET.
I'm guessing the trainer and energy cards are essentially worthless?
meh, some are, some arn't
I'll be super grateful to anyone who bothers to reply to this! I just went through all of my old cards in those silly clear card-collecting binder pages as this seemed the best place to ask that I could find.
Thanks!!

comments above in bold italic underline

[PokePop]

Those are not POP Promos. They are from Base Set 2. Not worth much since they are all commons and uncommons.

The Dark Persian promo, how many HP does it have?