When buying quantities of standard fasteners, such as screws or bolts, buy a full box anytime you will need close to a half box or more. The second half of the box will be virtually free. For example, 45 individual screws will usually cost about the same as a box of 100 screws.
When shopping for brass, take along a magnet. If the magnet sticks to the item such as a lamp base, it is not real brass. If the magnet falls off, you’ve got the real deal.