So I suppose you're looking for something with workstation graphics such as Quadro? These are tougher to find now than they used to be. I know Dell's business line still carries some. You can go for like a Dell Precision, they seem to be okay. Dell Precision Mobile Workstations
Medium to high end Toshiba Tecras Laptop still seem to come wit the Quadro Card. However that would really come down if you are trying to do any 3D Modelling. If I had to do that, i would be going for a desktop instead.
If you the OP is just doing floor plans, then WXGA+ display would be the way to go.