Welcome to the club. People are very unwilling to trade marquees, particularly the older ones. I've offered just about everything for a trade and no one is willing.
+1 most people want older marquees for older marquees or outlandish things for them. Prepare yourself for a hell of a ride because they're not an easy thing to collect. If you really want to collect them it's easier if they're the only thing you collect or else is going to be a pain. They're a thing of patience because they're easier to obtain when they come to you rather when you come to them. I'm not trying to tell not to collect them because they're really neat pins they're just a chore to get. If you want to be a completeist my advice to to you is to:
1. Work on them 1 at a time, it's a lot easier to do it that way
2. Work on getting the easier ones first then work on the the hards ones (if you go for the hard ones first it becomes really frustrating)
3. Save up some $ because you're not going to get all of them through trading, unfortunately you're going to have to buy some
4. Don't get in the mind set that you're going to get them all easy because it's not going to happen, there are guys who've been collecting them for years that don't have a complete set.
5. Have fun with them, they're really neat pins and the hunt for them is the best so don't let it bother you that you can't obtain a certain one, it'll eventually come.
6. DONT TRADE ANY THEM OUT OF YOUR COLLECTION, I've made this mistake twice. Don't trade one out of your collection to upgrade and get a better one. You'll regret in the future.
7. Don't ask people if they're trading any of their marquees out of their collection, again I've made this mistake and I've gotten on people's bad side because of it
8. Get familiar with other marquee collectors, we're like a little club and we tend to look out for our friends who also collect marquees. Sometimes we even go out of our way to get one for a friend (thats not the case with EVERYONE)
9. When you go to a PTN make them your main priority. I've gotten maybe 60% of my collection from PTN
10. If you get an opportunity to get one fairly easy TAKE THAT OPPORTUNITY, don't pass up an easy offer
11. eBay doesn't determine the value of them all, they're some (example: the first Narnia, Santa Clause 3, Bridge to Terabithia) that are rarely on eBay and plus the prices that they're going for always changes.
12. Get extra marquees for trading, most people trade marquee for marquee
13. Don't rely on the newer ones to get older ones since they're all le 500 most people who want them can get them easy.
14. Hoard some of the newer ones, just because they're le 500 doesn't mean they're not worth anything. Most marquees trade better in the future than in the present. Tron is a 500 and it's a very good trader