RetroGaming

Yeah as the other person pointed out, if you want an experience that’s up to you. The upcharging makes sense for a class as they’ve got a lot more overhead. The upcharging makes far less sense for an already modded gameboy sold on ebay or marketplace

For roms you’d want a flashcart. No mod there, just buy the flashcart, put roms on sd, put sd in flashcart, play. There are flash carts for literally every cartridge based console you can think of. Even the disc consoles (eg Dreamcast, psx, GameCube) almost always have something like an optical drive emulator the replaces the disc drive with an sd card filled with roms (these are less “plug and play” than flash carts though, which literally are just cartridges with an sd slot and some firmware to load roms)

Imo a flashcart is necessary. There’s basically no drawback, unless you’re specifically into collecting originals. Occasionally they can struggle with edge cases (eg games on snes that used superfx chips or games that used rtc like Pokémon) but at this point 99.9% of those issues are solved (except maybe if you get a cheap Chinese clone cart with unknown firmware. Everdrive is the standard but for like 1/3-1/2 the price you can get lesser known models or clones and tbh most of these are fine. It’s pretty urgent to check Pokémon or Mario rpg works when you’re developing one of these I’d assume