Yes, there's a certain flea market I go to every weekend. Two weeks ago, picked up a nice red tip for $12 (though I went back and paid $2 more voluntarily because the woman told me she paid $14) and a nice Slim for $7. This past weekend, struck out entirely. That's how it goes. But it's fast and I've gotten to know all the proprietors. They see me and will immediately say, "No razors today" or "Take a look at this" before I even open my mouth.
It's nice to establish a relationship like that. I've gotten a handfull of times to check out razors that came in. If you're already known for this, you're going to get them relatively cheap from them.