Each user has a different need. For many people, the Galaxy Z Fold 3 is a mobile workstation/backpack. It has everything you need to work, take notes, and attend virtual meetings. If this is you, strongly consider the S Pen Fold Edition -- either on its own or with the hard case. You'll be glad you did and might even wonder why you waited so long to do so. Indeed, there's something to be said about knowing you have everything you need packed neatly together in your back pocket.
If you envision yourself routinely listening to music or watching movies on your Galaxy Z Fold 3, opt for the Samsung earbuds. The sound is amazing, and it makes watching movies in bed at night that much more enjoyable. You get crystal clear sound without having to worry about whether you're waking someone up.
For us, the charging station is also a must have. At first it was simply convenient to not need three USB cables all of the time. Then it changed and became a necessity. Once you have it you never have to worry about damaged USB ports/inserts again, nor do you have to worry about whether your devices are actually charging when they're plugged in. The convenience is simply too great to pass up once you've experienced it.
At the very least, of course, you need to protect your Galaxy Z Fold 3 with a proper case and screen protector. We recommend the ones above because of function and price. If you don't need the pen, consider the see-through case because the Galaxy Z Fold 3's construction is simply so unique that it shouldn't be hidden. If you're a workhorse and need the pen, opt for function over design because having somewhere to store your pen can be a godsend at times.