Towards the bottom of your Buyer Requirements you can opt in or out of the pre-authorization requirement for Best Offers (still an experiment* as far as I can tell--only some buyer are subject to it, not all).
*ETA: And there are still major problems with it: It makes combining shipping a nightmare to impossible; it doesn't guarantee payment because the hold lowers the buyer's available balance with the funding source and often lowers it to below the payment required for the item and therefore the actual payment transaction doesn't go through because eBay submits it as a new transaction rather than closing out the pre-auth hold.
