Prepared 12 inch concrete pier and poured just over 1.5 yards of 5000 PSI stiff mix readimix for footing and sonotube with rebar. Construction time 1 full week plus 3 solid weekends. Plan to motorize dome. Floor on 6 inch plus gravel bed (mechanically isolated from pier) using 2×6 pressure treated with 3/4 inch pressure treated plywood as flooring. Ran underground UF wire in 3/4 inch conduit to observatory (240 V 40 Amp total capacity) for heating and potential AC. Will host 12 inch catadioptric. Interior includes observing platform elevated 42 inch above floor. Approximate materials cost including dome, gravel, and concrete $3,500.