Haha @West Oz Cards I don't think I have anything that could rival some of these but I choose these 4:
The first 3 are the 'has so much potential to be great' ones:
1. Donovan Mitchell Kaleido 1/1: This card is why I only have 1 arm and 1 leg. I used the other arm and leg to pay for it.
2. KAT Select Courtside Black 1/1: This was my first ever 'monster' I got from a box purchase. What makes this one so unique is that it's the only black 1/1 non-auto RC that has the 'x-fractor' effect from any product that year (or so I believe).
3. Jayson Tatum Cracked Ice Rookie Ticket: this card is fresh from a @West Oz Cards box break, Ben has been on fire of late. People have been going mad over the Contenders this year and the cracked ice parallel is probably the nicest looking and most popular.
4. LeBron James SPGU Rookie Exclusives /100: Personal favourite of mine, firstly because I wasn't collecting at this point in time (2003) and I somehow managed to buy this about 2 years ago for US$800 (which now looks like I should be answering questions with the local law enforcement). Anyway, was glad to get a proper rookie auto of the King because they are now so hard to get not even mentioning the prices!
Well I paid about $2300 for my Wilt PSA 8 several years ago on a PWCC auction.
Nowadays they go for about $8000...
I wish I could have afforded to invest in vintage more but I got the key cards I wanted in decent grades with good cantering. And glad I did when I did..!