This is a step-by-step guide to advanced hashish running. It assumes the reader is familiar with the basic mechanics of the game.
Step 1. Solo Ninja
You need to bite the bullet in Kenshi sometimes and grind out a training session. Create or find a non-Hive, non-skeleton character. It must be able to take acid damage. Groom it to be a ninja, getting around 70 stealth, at least 60 athletics, 60 thievery, and around 40 lock-picking. This does not take much time, but does take a lot of attention. I like to start the game this way, just to have it done.
Step 2. Stealing Limbs
Once you have a competent thief who can steal from store safes reliably, go to Black Desert City. It is located in the acid rain region in the center of the map. Steal 2 Masterwork Scout legs (L+R), and 2 Masterwork Industrial Lifter arms. The arms aren't as important as the legs, but the extra strength helps.
Step 3. Applying Limbs
There are several ways to remove limbs in Kenshi, and none of them are easy without cheating. The most effective way I have found is to blend two different techniques. Begin by having the limbs ready in your inventory.
To remove your legs, go hang out in acid rain and have a splash. After a few hours of screaming and complaining, your ninja's legs will pop off. You will either need to hang out in Black Desert City recovering, or have another character come rescue them. They will also need to spend some time in recovery, in all likelihood.
The arms are usually more difficult to do this way because of equipment parameters and the rate at which torso/head/stomach become damaged as well. I find it easiest to equip them with the heaviest and highest grade armor possible for all other regions and then to have the unguarded arms shot off by Dust Bandit Bowmen. A masterwork chain shirt and holy armor plate are ideal here. I would not do it with less than Specialist-grade. There may be better techniques. Please share them below if you know them.
Step 4. Buying a Companion
Buy a bull. Equip it with a bull pack. The age does not matter, you will be carrying it everywhere. You may as well be carrying veal for as much as it needs training. The bull backpack reduces weight by 90%, as opposed the the 60% of the ninja backpack, or 50% of most others. Because it also has the special stacking quality and is massive, you have more space and weight to carry hashish than the whole swamp could produce in a day, stacking several different multipliers on the ninja's natural strength.
Step 5. Time Passes
Grinding out strength can be painful, but stacking up raw chainmail or armor plate on a runner helps. Make your ninja a carrier for various jobs to keep him moving, then forget him for a while. Suddenly, you have about 60-70 natural strength, and run like Leto Atreides II. Note: These are rough estimates. By the time of this guide, my sneebler had stealth at 93 and athletics at 90. It may take more training before you can pull the whole thing off.
Step 6. Mule
You can buy drugs right into the bull's inventory. You can also traverse the swamp and nearby area much faster than anything else in the game. You cannot swim, so keep that in mind. Run your favorite circuit between all the swamp villages, buying hashish from fish traders and item shops (at the bigger villages, including Shark). It is a safe venture, so feel free to buy as much as you can afford/find.
Step 7. Sell
The best place to sell hashish is Flats Lagoon, without question. It is not illegal, and it is only a short distance East from the swamp. You sell it at a 400% markup, but do not need to sell to Shinobi and take the 50% cut. The shop owners buy it straight, and the town is densely populated with shops. You do not need to micromanage the bull, just carry it and watch if flap comically around. You can drain about 25k from each until you run out of stock. Altogether you can drain about 150k per visit to Flats Lagoon. Earn as much money as you have the patience to grind. Spend it at the Armour King. Lose interest in the game as money becomes irrelevant. Feed the bull.