Root Cellar - the author said it cost about $1,000 for this 8x8 foot cellar: concrete blocks were $1 each at the time, and he used about 320. About $500 for concrete and mortar, and the remainder for rebar, wood, etc. He contacted a local gravedigger to use a backhoe to dig out the space for the cellar.
Use of hollow blocks ( concrete here, could be terracotta , jali etc ) as an entire wall - to frame semi indoor outdoor space done very effecively. Possible low cost solution - privacy, windflow, aesthetic, Gerrit Rietveld pavillion at krollermuller museum via paulkomada
For a cost-conscious 2,000-square-foot renovation located 30 minutes outside of Austin, Texas, architect Nick Deaver took a look around for inspiration. He spied galvanized metal cladding on the region’s sheds and co-opted the inexpensive, resilient material for his own design.