A Full 8-Bit Gameboy Setup with all accessories acquired recently!

[vortalexfan]

Hello everyone, I recently acquired from someone at church an original 8-Bit Gameboy set that included its original case, several games in their original plastic boxes complete with their original manuals some earbuds, a 4-player adaptor, the original Rechargable Battery Pack and more.
The unit is in mint condition except that the screen was partially dead, which thankfully I had another Gameboy unit laying around that the screen was still good on but the case wasn't in good shape anymore, so I did a screen swap, and the unit is like brand new.

How Common were the 4-player Adaptors for the original 8-bit Gameboys and also how common were the Rechargable Battery Packs?

I'm trying to build up my Gameboy Game collection but I'm not sure what all to get, I'm a big fan of the Final Fantasy and Legend of Zelda series of games and also Dragon Warrior/Dragon Quest series, and the Mario Games, but I'm not sure how many titles there were from those game series were released for the original Gameboy.

See pictures below.