Hot take: My first deck build involved a tape measure, a dream, and zero square corners
Back before phone apps could check for level, I eyeballed everything and trusted a old bent ruler. The finished deck had such a wild lean that rain pooled in one corner like a tiny lake. We called it the 'pirate ship patio' for years until I finally redid it with proper tools. Now I just punch numbers into a calculator, but I kind of miss the creative, if shaky, results.