When you get a lot of donations, it is easy to want to put them all out. But it is actually best to not have too many silent auction items - an increase in quantity does not necessarily lead to an increase in income!
If you have tables upon tables of items, your bidders will not get a chance to see everything that you have to offer. Many will stop looking before they get overwhelmed or feel over committed.
Make sure the items that you do have are well spaced and in a well lit area. Having a manageable number of items will make this a lot easier! Viewers will have no trouble seeing what is available and what the current bids are.
So how can you make sure that all items are available? Bundle small items into gift baskets. It will also prove much more cost effective than your staff having to process an overload of small value items.