[bluGill]

Double is probably a low estimate. There is a lot of engineering required in the robot. Much of the effort is setup, someone still needs to bring it to the site, and feed the blueprints in. Cleanup is also a lot of the cost. Not to mention mortar is made of sand which is abrasive and will wear it out fast meaning lots of maintenance work.

Working day and night isn't helpful as the limit to speed is waiting for the mortar to cure before doing the next row. (Generally you do about 5 rows and then wait a day)

[rootsudo]

could the robots not do more than one site? 5 rows, move to other side, a house if rectangle does have four sides, and a subdivison has multiple houses?