For your semi-auto rifles, the brass will grow in length when you resize it. As a result, you need two things: case gauges for each caliber and some kind of a case trimmer.
Just to get calibrated, go to Brownells.com and search for 'case trimmer'. There are quite a few and the prices are all over the map.
Personally, I use the Hornady Case Prep Station but there is no need to get that carried away. In fact, I'm kind of surprised I bought one:
It's a nice unit but it isn't, in my opinion, nearly as precise as the Forster stuff. However, for bulk loading of .223, perhaps absolute precision just isn't required.
The case gauge will show you whether the cartridge headspacing is correct. Headspace is the distance between the midpoint of the shoulder (up the slope) to the base. In other words, it helps you get the resizing die adjusted. It's nice to know that the case is properly resized.
The case gauge will also show when a case needs to be trimmed. Resize first and then check with the case gauge.
I have case gauges for my pistol cartridges as well: 9mm and .45 ACP. It makes me more confident that my reloads will chamber.
If your dies are properly built, they will automatically produce minimum headspacing when adjusted all the way down. This makes the argument that a case gauge just isn't necessary. I would rather have them.
You will also need a set of calipers. I don't care if they are dial or digital except... I bought a couple of inexpensive digital calipers from Harbor Freight and they get the wrong answer. I need the right answer so I am back to using my Craftsman dial calipers. Now, the difference was only 0.001" and for measuring OAL, who cares? But when I wanted bullet diameter, the digital calipers came up short. Buy a decent set. They will be around for a very long time.
A suggestion for your 9mm reloading: Tumble and reload. Don't bother cleaning out the primer pocket, don't bother trimming, do check the loaded rounds in your chamber (with the barrel out of the gun), they should go 'kerplunk' when you drop them in. They should then rotate easily on the case mouth only. The bullet should not drag on the rifling.
Since you have carbide dies for 9mm, lubing isn't strictly necessary. However... Buy some Hornady One Shot lube anyway. Dump all the cases in a plastic box (one layer thick) and squirt them lightly with the lube. I shake up the box to spread the lube and after about a minute, I reload them. Resizing will go much easier with a little lube. Don't bother to clean it off. If you want to clean it off, tumble the loaded rounds.
Don't overthink the 9mm stuff. Just load it! Be very careful of the powder charge. Everyone around here is going to recommend you start with Unique. That's ok but you will find that you can't hold +- 0.2 gr. As long as your not up near max, it really won't matter much. If you are too close to min, your slide might not cycle. Just keep it in the middle of the road. Throw a lot of charges just to get into a pattern. Weigh them and see how consistent you can get.
If you were using a 115 gr FMJ, the charge for Unique (according to Speer #14) would be 5.6 gr minimum to 6.3 gr maximum. It looks like the 5.6 gr charge would make IDPA power factor so that's where I would start. I might
work up toward 6.0 gr but, with Unique, I might stop at loads 0.2 gr away from max.
There are a lot of other powders but most everyone around here likes the safety in using a slow powder. Especially for new reloaders.
You can skip the case trimmer until you start loading rifle. I would still get a case gauge for the 9mm even though your chamber is the ultimate authority. In theory, if a round fits the case gauge, it should fit any gun around. In theory...