What programs will she be running? Many creative programs are optimised for nVidia Quadro or AMD Firepro which you miss out on if you go with one of the cards more geared up for gaming and general use.
If you are not using programs that can use those types of graphics card you might not get much benefit from an extra card over the graphics that are now built into the i7 chips.
As Cougar say you won’t save much on a home build unless you really cut corners which I wouldn’t recommend for a machine that might be left on quite a bit rendering video etc.
If she will be doing this casually then I would just look at a system from someone reputable like Chilliblast: Chilliblast workstation
If you want more mainstream the I can vouch for HP workstations, the build quality is pretty good and they start at reasonable prices e.g. HP SFF workstation