Being slightly old school I can only comment as follows. When my brother and I were doing, kitchens, bedrooms, patios etc., we used laser a lot but relied on the fact that we either had a solid background or similar where there were points of reference. Not sure how laser can pick up midair as it’s an indefinite beam. I can only assume that you plan to drop the overall height by a margin to enable the beam to function. Even then, as soon as you cut the first section along the beam, then the beam will disappear into the ether. Only my opinion. Jok.