Star Trucker

The easiest way to do this is to play on ‘CUSTOM’ settings,

You can customise the settings however you like but for this achievement specifically, put the following to help with this achievement:

(General)

Item Damage: Low

(Finance)

Starting Balance: $25,000

(Economy)

Shop Prices: Low
Tolls: Low
Repair Costs: Low

There are many other settings such as putting the job payouts/bonuses to High and putting the job deductions to Low , but have a look at them all and adjust them to how you’d like your gameplay to pan out.

Method

The best way to get this achievement from what I’ve experienced is to visit traders and buy all of their stock from them. Once you’ve purchased everything, get up from your chair and head on over to the airlock front door in your cabin. There will now be a basket icon on the front door with all of your items you’ve purchased inside. Click on the front door with the basket icon and sell all of your items back to the trader. You’ll have to click on each item individually that you want to sell then hold to confirm.

You’ll make a slight loss but sometimes you can sell them all back for at least $10,000

You’ll then have to wait for that specific shop retailer to restock their items. A set time will be on the traders stock side of the screen indicating when their stock will be back. I believe there are at least 2 different trader retailers but their could potentially be more across the galaxy.

Rinse and repeat this process and you’ll be on your way to earning this achievement along with the other 2 achievements related to making money from trading!

Hope this helps!

"Buy low, sell high"
This game incorporates a system very similar to Drug Inc. from way back on Newgrounds.com.
Each sector has higher or lower local prices for every product available at supply stores. These percentage changes can be found on the map. Purchase things that are on sale, then head to a nearby sector where the prices are higher, and sell. This can be planned in conjuction with transport jobs, by checking the route and stocking up before hitching to the cargo.
The same principle will work for the contraband achievement.

"Buy low, sell high"
This game incorporates a system very similar to Drug Inc. from way back on Newgrounds.com.
Each sector has higher or lower local prices for every product available at supply stores. These percentage changes can be found on the map. Purchase things that are on sale, then head to a nearby sector where the prices are higher, and sell. This can be planned in conjuction with transport jobs, by checking the route and stocking up before hitching to the cargo.
The same principle will work for the contraband achievement.