My wife and I are about to DIY a paver patio about the same size as yours. By far the least expensive pavers are concrete pavers (rather than brick, stone or tile) . . . but concrete pavers looks a bit generic, so we’re going to stain them . . . and we’re going to use a mixture of 16″x16″ square pavers and 16″x8″ rectangular pavers, available from the same manufacturer at Lowes . . . to create a more interesting look. Lowes also has a flat-rate delivery fee, so we’ll be ordering gravel from them as well. Good luck.