I think Pokemon carts are too expensive (there are tons of these available). I won an auction that included Red as a part of a bundle that included a GBA, a case for it, the Pokemon cart and maybe anpther game or two. I paid more than I feel it was worth, but it was still cheaper than what Pokemon games alone usually go for. I don't know where my original cart went, so I feel it was worth it, not that I am really into Pokemon. If I need a bit of quick cash I can always sell it.
I have had a hard time collecting carts since the games I want are plentiful but have a high demand. Zelda ones are really bad, so I was lucky to get most of mine in trades or by doing repairs on "dead" carts. I think my Link's Awakening is my original. If not, it and many of my others are probably at my father's house.
My grandmother used to have most of my NES collection, plus MANY others she bought to add to our collection. No clue what happened to that. Metroid 2 was one of my earlier GB games, so I wanted to get another copy and found that they are slightly pricey here compared to carts from other countries. I don't have my old one so I waited until I saw one kinda cheap and got it.
I am not a collector of the sort where I "gotta catch 'em all", I just want the ones I want to play. Due to the high prices of games that are available in large numbers it may be better to skip dealing with that bullshit and visit ED's other shop and get an everdrive. I really don't understand the point of buying a game to never play it. I also play with my toys, read my comics, play with and look at my cards, etc.
"Oh, this $5000 meal is not to be eaten, it is to add to my collection." Or wine, etc. At least car collectors drive their collection sometimes, I think.