W-9 forms and 1099 Misc. for corporations

[Danita Francis]

Hello--we have all of our contractors fill out W-9 forms, however, as a first year rehabber, I'm wondering if I am supposed to ask the larger corporations, specifically Empire Flooring in this scenario since they provided installation as well as material, to complete a W-9 form?  Or what about granite installers, who provide installation as well as granite?  Can someone please give some insight on this?  TY