He's a Doctor in Disguise
Maybe you've heard that a pregnant woman often develops a crush on her OB/GYN, since he's the one taking care of her and calming her fears during a vulnerable time. Renovating creates a lot of stress and uncertainty, too, and as with giving birth, a woman's never entirely sure how the process is going to go. The contractor knows how to safeguard and improve the workings of the house; he's seen it all, he's capable and calm, and he can talk her through the endless procedures being performed on her home. He can assure her everything will be all right.