I've said no twice. I had been looking for a modern .45-70 and finally found one. It was a New England single shot. It was $300 and had a wood stock. It needed refinished and the hammer felt really weak. I walked away from it and bought a Marlin Goose Gun instead for about half the price. About a month later at a gun store after work me and my dad was looking around. Apparently someone had sold them their H&R/New England collection. They had a very new looking New England 45-70. I got it for $200 and dad bought a 30-06 H&R.
The other time I had to say no was I had been looking for a 10 gauge. It's pretty hard to find. Well, I was at a gun show and found a New England. I can't remember the price, I think around $300. But it was an older model with a fixed choke and someone had painted it camo. Although I wanted it, I walked away. About a month later at a gun show I find a Stevens single shot 10 gauge with a 36 inch barrel and a full choke and paid $200. I refinished the wood and cleaned the gun up and looks perfect nearly.
So, it goes to show walking away can lead to better deals.
On a side note, I shot an AR yesterday. We are doing work on a house and the home owner let us shoot his gun. I now understand the hype, still wouldn't buy one though.