A good camera & steady hand. Learn to use the macro setting - prolly looks like a flower on your settings menu. Take plenty of pics until you have some GOOD ones in focus and well-lit. I also suggest a white-box. I think someone posted a link to making one over on RS a few weeks back.
I promise you - a GOOD pic and accurate title WILL bring you more hits and bids. If you are selling Star Wars toys and listing them in the Star Wars categories - WHY do you need to put "Star Wars" in the title, hm? That's 9 letters you can use to better title your auction.
Clint, have you tried asking at local furniture or electronics stores for styro or sheet foam? That just occurred to me. I need to ask the local furniture store about foam for dios...
Write your description up in Wordpad or something first, then save it and c&p it into the description area.
Keywords in the title are your best friends. Have I mentioned that? I grabbed an Aayla Secura for $3 this week, because his title was "loose female jedi." Now, I'll grant she's hot, but I don't know about loose!
I watched two other auctions for the SAME FIG go over $8 each - loose - because they both had "Aayla Secura" in the title. (he also had a really crappy, underlit pic of the fig - he didn't do himself ANY favors in that auction)
Include the line/group/whatever they call it in the title - POTF, POTJ2, VOTC, Saga, OTC, etc. I want some of those neat "force effect" pack-ins that came witht he Saga Yoda, so I look for "Saga Yoda" and can weed out the other yoda incarnations.
Make it a note in your description - remember, the one you saved earlier? - that you recycle packing materials *to save your customers money*! If you don;t have to buy the material, you don't have to charge s&h!
Forget the postage meter - that's what the folks at the PO get paid for. Unless, that is, you live so far out in the sticks that driving to the PO is a major hassle or if you just can't get there during the day.
Take your pics as flat/square to the subject as you possibly can. I hate trying to decipher which fig it is third from the left in the top row because the camera is tilted in such a way as to make identification impossible. Same for flash-glare. Use a light-box and extra lights so you don;t need the flash. Glare sux.
Good titles, good pics - that's all you need. IMO.