Probably a lot less than So Cal. Just starting 1 today. We already did 33'. Extending it 72'. Retaining with 8x12x16 block. 2'x4' footing. City just approved it. $375 a linear ft. 5' tall
Going to piggy back the wall at my house along with it. Not Retaining and 6" wide block. Hoping to get mine done for 75$ a linear ft 6ft tall.