I also work in finance but for luckily, I was collecting baseball cards for ten years before I got into finance so I am able to separate the two thoughts. I have, however, found it to be a struggle to not think of 'future gains' before I buy a card, but when I find the card I 'need', I am able to purchase it even if I believe I am buying the card at the 'high end' of the pricing spectrum. I basically separated my collection into the 'investment' portion' and my 'personal collection' portion- problem is, 99% of my higher valued cards have found their way into the 'personal collection' portion so my 'unrealized gains' if you will, will probably continue to accumulate
