I find I can work quite well with a wifi hotspot (mine is ATT and I'm very, very surprised that latency and transfer speeds are non-issues) and my laptop.

However, that's basically my home setup as well, just with normal home internet service.

I have a power adapter to give me a power plug in the car for the laptop. The hotspot can usually go over a day and charges with the same cord as my phone, if I need to charge it up.

Maybe you can use virtual desktops instead of multiple monitors. They come standard in Ubuntu linux, which I run, but there's a good program for windows that does the same thing.

Edit: I'm a web developer, if that matters.