Everybody has their ideal way of way of working remote, the best I can do is go through all the variations I've tried in the hopes that one or some combination of the methods will help you decide what you need and don't need, and what works best for you.
A quick overview of the methods and options..
Option 1 - A traditional laptop with no accessories; the bare-bones version of minimalist travel while still being able to work; if you're lucky enough to have mastered the tiny keyboard, touchpad mouse and the eye-straining screen, you are truly blessed.
Option 2 - A traditional laptop with one or two external monitors, and a wireless mouse and/or keyboard to round out your setup; this is about as close as you can get to a work-from-home setup while maintaining a high level of mobility and productivity.
Option 3 - An iPad or Windows Surface Pro as a laptop alternative; just a step down from a full-on laptop, you get much of the functionality of a traditional laptop, in exchange for a slimmer profile and footprint.
Option 4 - The phone-as-a-laptop "dream" setup; instead of lugging around a laptop, why not use the one in your pocket? There are a number of early-stage options for phone-as-a-laptop setups, and I'll go into the details of each below; in short, it's a work in progress.
Option 5 - Work from your phone; if you've mastered the art of working from your phone, you're already on another level, and I am jealous; for those who haven't, check out some of the tips and tricks below.
Option 1 - Laptop with No Accessories
You're ahead of the game and there's not much I can help with here, other than perhaps a few honorable mentions such as a dry sack or waterproof laptop bag.
Option 2- Laptop with External Mouse, Keyboard and/or Screen
Check out SideTrack for a number of attached or detached external monitors, or search "portable travel monitors" on Amazon for various options; you may also want to consider a protective case for whatever monitor you go with.
Option 3 - iPad or Windows Surface Pro
Option 4 - Phone-as-a-Laptop Setup
Where others have tried and failed... I have... also failed.. and it is extremely frustrating..
The best I can do is suggest checking out a few YouTube videos on the topic; if you're rocking an iPhone (as roughly half of the US does), you'll definitely need/want a Lightening-to-HDMI Adapter, and if you're constantly being ridiculed for your green Android texts, perhaps the Samsung DeX interface will eventually help turn the tide.
If you decide to take the phone-as-a-laptop approach, you'll need an HDMI-compatible monitor, a wireless/Bluetooth keyboard and (most likely) a wireless mouse.
Lastly, there are a few other options for using your phone as a laptop that I haven't researched or gone into specifics on; if you're tech-savvy and willing to do some additional leg-work, check out https://www.makeuseof.com/tag/ways-turn-smartphone-into-pc/ for additional options.
As an alternative to Samsung DeX, consider packing a Google Chromecast
Note: This post is a work in progress, check back later for more updates and details.