The most common thing that you have to fight, they are varying in strength depending on the region you're in. However, police and Desert Patrol will kill them on sight. More information is available in the Enemies page.
For robbers, I would generally label them by their "sectors", which I define as the four parts of the map. Note that my strategies are assuming that you have the best weapons first available when you get to each sector (as in you only have the M1 Garand in the Poca Cosa, the M14 in the Verdamnter Platz, rockets/machineguns/snipers and everything else in the Qubba region and the Sekir Bashka/Abu Kirdyk region.)
Generally, the Poca Cosa region has bandits that have only small pistols and close range weaponry, and basically never appear in groups larger than 4 and never have any kind of animals, carts, or vehicles. Fighting these with lowgrade weaponry such as SMGs and pistols, or the default rifle you get from your "uncle" is simple and very low risk. Its practically impossible to lose, even if fighting them with knives/swords. The trick with these is to move at them till they are within about 30 to 40 meters. Shoot with aimed shots. Once within 15 meters, quick shots are great.
The Verdamnnter Platz region, which extends to include Okaidi and its area, can appear in groups or usually around 7 robbers. These are typically armed with a mix of close range and small rifles, the larger groups can sometimes have 1 or 2 assualt rifles. These have a small chance of having animals and carts, which is a nice bonus. They don't have vehicles, and so are hunted down by the Desert Patrol very quickly. Fighting these with SMGs and Assualt Rifles are best, although a few Rifles could manage barely. Watch out for groups of very high AP bandits that carry Katanas. These people can travel 10-15 steps, and if they get you close, you're dead. They also are very hard to kill, takes multiple shots (3 or 4 from a high powered weapon) just to kill one. Still, they aren't that threatening except in the very beginning of the game when you first travel from the Poca Cosa area to Verdamnter Platz. Here, the robbers are seriously annoying. Best to take out as many as possible. Move to those gaps between your animals or between your cars. Sit there and keep using aimed shots till the enemy reaches 25 meters away, then quick shots and 3 round bursts (5 round burst is too wasteful). If they get really close, then run like hell or risk it and 5 round burst them.
The Qubba region is somewhat more dangerous. Robbers vary from 8 to about 13, and 15 is the most I've ever seen. They usually don't have vehicles, sometimes have animals/carts, and are armed with low-power guns such as rifles and SMGs. Weak, and slow. Take these down with snipers and assualt rifles. In the worst case, you can always launch a few rockets and rip apart groups of them at once. These are actually quite deadly, even later in the game, but a well equipped group (say, M14s at the very least for everyone) can take these down fast and without casualties. Sniper is preferred for accuracy, range, and damage, but assualt rifles work fine. Most of these robbers are immediately hunted down by police, anyway. Start the same as the above. Hide directly in between your cars and aim at the enemy. First, pinpoint the enemies with rockets. Hit them fast with your own rockets/sniper fire. Once the rocketmen are all dead (hopefully they don't get off a shot at you), use machine guns/assualt rifles to mow the rest down. Or, if you're scared, use more rockets and perhaps grenades. Moving away from these people is NOT an option, save as much AP as possible to shoot your guns.
The robbers in the Abu Kirdyk region are deadly. They travel in large groups, sometimes even up to 20 robbers. They always have vehicles, usually Artic Cats ATVs or Yamaha Raptors. Fast, and annoying, they are armed with heavier weaponry. Every group has assualt rifles, which are seriously deadly when they've got 15 men with assualt rifles. The largest groups have RPG7s and Bazookas, very rarely RPG29s. They also have machine guns. When fighting, snipers and rockets ARE A MUST. Take care to shoot the enemies that have rockets and machineguns first. Assualt rifles don't quite work against these guys unless you've got more people than they do. The only two things that kills these robbers reliably and fast are snipers and rockets. Make sure to have 2 or 3 rocketmen before heading into this area, and preferably arm the rest with snipers. If not, then machineguns or assualt rifles will still work, just not as fast. Same as Qubba, but this time use ONLY rockets if you can (or grenades). Don't think "oh, I can pick them off with machinegun bursts...", because these robbers just love to hit you when you don't notice. I've been hit with multiple rockets before just because I didn't pay attention and see the rocket robbers hiding behind a car. Snipers are great for picking off those rocketmen, however, and use the rockets on every group of robbers. (Just don't use rockets on single robbers standing alone).
The general idea of it is that to be a fully prepared team for everything, equip all your men with Military Armor, snipers, and rockets. Assualt rifles shouldn't be used too much, they don't have the accuracy you need to take down enemies quickly and efficiently, nor the large burst fire of the machineguns. Keep 1 or 2 anyway in case, however, as snipers/rockets have horrible clip sizes. In case you don't feel too confident, a nice technique is to hire really bad people, equip 'em with nades, and have 'em run straight at the enemy. But this should only be used on the boss battles. Otherwise, follow the above.
Questions at my account (Whirled), or my email: firstname.lastname@example.org
(from a random man)I like to disagree.My 5 man group can take many hits from the LARGEST traveling robbers and suvive.The only problem are the many robbers in the area.Before I could see them there are already 15-20 groups on my tail.But I won't disagree on one thing, Those robbers ARE dangerous for caravans.If you are not prepared you will never win.I just lost 2 of my men to THEM!I hate those robbers.