One good thing about having some of the guns I want is that I can be a little more patient now. If I don't get the deal I want, I don't buy. I can negotiate down and not feel bad if it goes to someone else. I make sure not to underbid on what I really want... but how important is it to have that 11th or 12th gun? It was $200 important 3 months ago, and $150 important now.
There is an RWS 54 that looks near new that's been on the AAC for months. In that period of time, I looked at it, thought it was too much, bought a 350, traded it for a 48, and while it isn't recoiless and I had trouble with the deal I still think I'm in a better place. And the 54 is still for sale, I don't think the price has come down but $25. I got a Cometa Fenix from before the post RWS 94 appearance update, brand new for $140 shipped. I didn't need it. It was up for $190 plus shipping and I put in a bid explaining what the gun was worth to me. I told the seller he'd probably sell for more if he waited, but the offer stood. A few days later I got an email $10 over my offer, and I couldn't turn that down. If I bought new, I'd have to pay $350!! On the other hand, an RWS 94, virtually the same gun, was up for sale for $10 less than my offer, and the seller wouldn't post pictures. I don't have time to fuss with that kind of seller now...where I might have before.
On the other hand, I regret having found too many deals before I saw Gene post a Ruger Air Hawk for $200 with full tune, custom stock, and muzzle brake, as having a Cometa that he tuned I know the quality of what he keeps in his collection. Were I less 6 guns and knew more 6 months ago, I'd have been more picky on the way to where I am, but I'd have less experience with what to shoot...sort-a catch 22.
If it is something I really want, I weigh it against what I have to get rid of now. I'll pay it, but it has to be special. And sure I've missed a few, but I'll get an even better deal if I am patient and look for the right one.