For the price they'll spend on an ultra-high-end laptop (I'm guessing stuff that meets their requirements will be in the $2000-3000+ range), you can get a mid-low range desktop that still blows it away in performance AND a midrange laptop you can remote into the beast with.
I stopped buying high-end laptops long ago. I do a lot of Android platform development in my spare time - most of the time I do it on a Chromebook running Crouton, remoted into a quad-Haswell i5 buildbox with 16GB RAM and multiple 256GB SSDs. (Actually, I ran out of space, so I'm putting in a 480, retiring one of the 256s or expanding the ccache size.) (Note, by "remote" I mean "across the room" - the assumption is that laptop and desktop are on the same LAN. I intentionally made my buildbox small in order to make it easy to lug around for car trips. I didn't get it small enough to suitcase in checked baggage, should've gone mini-ITX for that.)
The initial investment (single SSD) for the buildbox was $600-700, and that was around a year and a half ago.
A Dell Precision M2800 that barely matches what the buildbox is capable of (actually, it's significantly less capable CPU-wise due to thermal limits, 2.9 GHz nominal instead of 3.4 GHz nominal, for sustained loads turbo is useless.) costs $1799
Note that the assumption here, based on what the OP has described, is that the system will primarily be used for CPU/RAM-bound tasks, not GPU-bound.