My experience is that dealers are looking to bring in some cash to pay for the table, other expenses and make some money. However, trades are sometimes possible if the dealer either collects the item you're offering, or at least specializes in that type of item. For example, instead of trading an item marked $25 for your item that typically "books" for $25; you might be offered $15 or so in trade credit for your item.

Also remember that the marked prices aren't always set in stone. You can negotiate some, especially if buying several or more items from the same dealer. There won't be much room to negotiate on $5 LE's marked $8 each, but on some higher priced or lesser-demanded items, you can probably get a discount at most tables. One tip: know what a "fair" price for certain benchmark items should be. If the dealer routinely has such items market above market, he may be building in a negotiating margin. You can also shop around for items that may be found on many dealers' tables.

In the past, I have paid list price for quite a few items, but have negotiated on quite a few also.

One last tip: while some dealers re-mark their chips based on the ups & downs in recent value, some dealer stock prices may be obsolete (on the low side) and you can occasionally find some bargains, even at list prices. (This doesn't happen too frequently, but keep your eyes open. Even "junk boxes" can have a good find.