How have you gone about upgrading your existing collection

[MCoxon]

These are great stories, I really appreciate all the posts.

I am wavering on upgrading because I worry it's just one more step on my way to hoarding, vs. getting truly new, exciting cards. On the other hand, because I've limited my collection to player sets I'm starting to run down on available pickups. I'm wondering about doing what a few have posted about - going back to sets I first collected as a kid (which would be 1979-1983, baseball and football)...

I did take a step since I had a few days off this week - I went through my entire PSA-slabbed collection and made lists of singles to upgrade. It's never a good sign to commit to a want list in excel - with my personality it means I'm likely to get them.

[steve B]

My upgrading has been haphazard at best.

For years I'd buy cards that were not exactly in great shape. Except sometimes I'd get nicer ones. I just wasn't picky, so whatever seemed like a decent deal at the moment was what I bought.

Now I try to get nicer examples, especially of commons. And while I have some checklists/spreadsheets (The spreadsheets are just checklist grids) I don't bring them to shows or flea markets. So I get a few that I already had. I just compare and swap in the nicer ones. Occasionally I can't decide. Perfect centering but with a crease or bad corners - Or the one that has almost no wear but isn't centered. Sometimes I just keep them both.

[swarmee]

COMC can be pretty useful in this endeavor. Since they will store your cards until you decide to take ownership of them, and you can resell on their site, I buy/sell cards there.
I'm working on 1952 Topps and Mickey Mantle cards right now. I can buy them from their site, leave them in my inventory, and then if I see one in a better condition for a reasonable price, I can buy it and then relist the first one I bought.