1 A retired Regular officer who also is employed by the federal government and is subject to the dual compensation statutes may have that reduction reduced because of the waiver of retired pay to receive VA benefits.
If they don't, then 4 thick is usually standard for a patio slab, how large or small it is doesn't really matter. The most important part is the sub-base. Make sure you have a good gravel base. I would recommend at least 12 inches of compacted gravel. I like gravel where the aggregate (rocks) are no larger than 1.
We want to expand our existing patio. It is solid, level, no cracks. We will increase from approx 16x11 to 16x24. Realizing there is no way to have a standard pour match the old concrete we want to end up with a uniform decorative look, such as a flagstone design over the entire patio.