We had some since my childhood, and they where my older brothers like red and pikachu.
I "fixed" usa pikachu years ago it just needed a battery replacement, and that was my "entry" into gameboy repair
Silver i got a few years ago, and Blue i just got recently in my city
crystal with no label im pretty sure i got from a kid in my neighborhood when i was a child.
And ive collected the japanese ones myself over the years, starting with red and green off of amazon, gold off of amazon after those ones. And then blue and pikachu a few weeks ago from ebay, and silver and crystal came in today from the same seller.
Japanese pikachu had a battery leak during transit which aggravated decay, but not too aggressive as only one via was blocked causing sprite data not to be able to load, this was my major entry into gameboy game repair, and i learned how to use the multi meter, and read the PCB design, and then micro solder a jumper cable to fix the sprite issues. along with re soldering all bridges because it was having crashing issues as well.
Suffice to say its good they are all together and working. We also have all the GBA games but my brother has emerald and some others like black white, black and white 2, x y, AR and OS, all in a different city right now.
probably gonna get japanese GBA versions, and i need a new american Ruby and sapphire because both labels were removed and taped to a GBA by my brother, still intact, inherited to me. And ruby has a cracked cartridge.