First things first in buying laptops- make sure you're getting one with a really good processor/processing speed and a good amount of RAM; anything under 8GB of RAM(although you really should be getting 16GB of RAM) is a waste of money unless the laptop has the capacity to add more memory to it.
Depending on the number of devices you need to connect to it, make sure the laptop has good and varied number of connections/ports. HDMI(if you want to connect it to an HDMI monitor or your TV), USB 2.0 or 3.0, SD card slot, USB-C(which is one of the reasons I need to upgrade now- my new screened tablet can connect via HDMI or USB-C; I have an HDMI monitor that is more or less useless right now coz I'm running the tablet through the HDMI connection).
3rd, make sure it has enough hard drive space; art files eat up a LOT of space- not to mention reference files & other stuffs...you need to at least be getting 1TB [or more] of hard drive space. Also invest in an external HD, so that you can back up and move files there...if your laptop crashes, at least having an external backup HD will save you a heart attack.