Would someone in the greco-roman world who'd want to have a house built have a sketches done by architects, decorators, and others to see and approve of the work to be done beforehand?

by CouldHaveBeenAPun
BaffledPlato

Yes, at least for more substantial houses. The Roman architect Vitruvius states this explicitly:

...[An architect] must have a knowledge of drawing so that he can readily make sketches to show the appearance of the work which he proposes. (1.4)

He goes on to explain exactly what kind of sketches and plans are needed:

A groundplan is made by the proper successive use of compasses and rule, through which we get outlines for the plane surfaces of buildings. An elevation is a picture of the front of a building, set upright and properly drawn in the proportions of the contemplated work. Perspective is the method of sketching a front with the sides withdrawing into the background, the lines all meeting in the centre of a circle. All three come of reflexion and invention. (2.3)

A number of years ago I answered a related question regarding blueprints and plans, so here is a bit more information : In ancient times, were "blueprints" used to build structures such as the pyramids in egypt, the colloseum in rome, the tower of piza and so on? If so, have we found any of the plans used on these ancient architectural marvels?