I've been trying a lot of different ways of playing Minecraft over the years, one that I have never tried is playing on a big multiplayer server with a custom currency. I watched a few videos to understand the concept and then ended up finding a different way to get from $0 to $100 million: auction house flipping.
$0 - $100k
At the beginning you start with $0, I spawned right next to a pillager output and killed the raid captain for an ominous bottle. Turns out they go for ~$100k at the auction house. So I sold this and got going.
In practice I ended up selling a few boats, tried to start a wool farm with sheep but that turned out to be a big waste of time.
$100k - $1 million
Shop Items
One of the thing that realized very late: you can go to the /shop and buy Bottle o' Enchanting for $6.4k a stack and then sell it for ~$20k in the shop depending on the time. Many people don't realize you can buy for very cheap many basic components and they buy them from the auction house instead.
As a result, you can get ~$15k per stack as long as you don't get into a war with somebody undercutting the prices. I looked at all the items sold in the shop and the blaze rods were the only other ones I found that had enough trading volume and the market price was significantly higher than what you could buy.
Bonemeal
Bonemeal trades at around $10k per stack but you can craft it from either 1 -> 3 bone and 1 -> 9 bone block. It turns out that in practice people buy bone meal at around ~$10k and bones at ~$15k (~$15k profit) and bone blocks at ~$50k ($40k profit).
This was pretty labor intensive do to this as there's a huge trading volume on bonemeal so you are constantly buying, crafting, selling to the auction house and checking out price of the competition but was pretty low risk and high reward.
$1 million to $10 millions
Redstone
The idea of buying large quantities at a cheaper price and selling it in smaller batches kept going on but with more expensive items. This time it was with redstone block -> dust.
In good times I could get a cheap stack of redstone block for ~$120k and resell the redstone dust for $25k. The price for these were fluctuating widely from ~$100k at the lowest to $300k at the highest for a stack of redstone block. Buying low and selling high was also a viable strategy.
Ominous Bottle
My first sale was for an ominous bottle and found out that this is very lucrative market. People are buying single bottle every tens of seconds and people don't really know how to price it so sell it for ~$10k to $80k naturally.
I ended up monopolizing the market. I put up my bottles for $97k each and would buy every single bottle people put under that price. As a result my prices were always the cheapest and I would make a profit for all these eventually.
At max, I accumulated 30 bottles of inventory (~$3 million) doing that but thankfully nobody really tried to go on a pricing war we me there so I was able to control the prices while I was active!
Dispenser Farm
All the youtubers are building out farms so I figured I'd also try it out. It's soooo painful to manually craft dispensers so I built a fast crafter setup for them. One bad news is that DonutSMP has a custom alteration that makes hoppers way faster and push 4 items at a time. As a result none of the off the shelves farmed worked anymore. I spent a few hours tweaking the design for it to work.
It did work in the sense that I was able to buy a shulker box of the items in bulk (cobblestone, logs -> sticks, redstone, string), run the farm and make a profit.
In practice however, this took a bunch of time to buy all the ingredients, craft the sticks, put in the chests, fix the crafter recipe... I found out that all this time I wasn't flipping and making money.
In the end, I ended up buying entire shulker boxes of dispensers from antidemir and flipping them instead. I sold a stack of dispenser for ~$250k so about $6.75 million per shulker box, for a $2.75 million profit.
$10 to $100 millions
/Orders
One thing I found that changed the game is that not only you can put things to sale, but you can also ask people to sell you things. In practice the rates that people are willing to sell you things are significantly cheaper than what you can sell on the auction house.
For example, I bought 14 stacks worth of redstone blocks for $146k each and sold them to ~$300k making a ~$2 million profit on the order.
Blue Ice
At this point I needed to find more expensive things to flip. There's a limit of 25 items you can put on the auction house at once. So in order to keep scaling you need to find items where one stack can cost more and more, you can buy them / transform them cheaper than what you can sell and there's enough volume to not hold the inventory for too long.
I found Blue Ice to be pretty good. There's a sizable demand but not a ton of sellers so it was a profitable endeavor. I would get orders for ~$70k a stack and sell them to ~$150k - $200k making a good profit.
Strategy
The strategy in general I used for selling was to figure out what is the lowest price of a bulk of items and put it just a bit less expensive. If I see that there's just a handful of items cheaper, I would just buy them to raise the floor of the price to mine.
If the price was too low to make meaningful profit, I would wait it out and focus on other items to sell. In practice I ended up having 2-3 types of items I would sell at a time focusing on the most profitable ones and the ones I had an inventory of.
In many cases people would start lowering their prices to capture the demand. I notice because when you are the lowest price, there's tend to be a stream of sales. If they stop, it usually meant somebody undercut me. I could either wait for them to sell out or remove all my items and put them on sale one notch lower and repeat.
Conclusion
Buying at a low price and selling at a higher price was a surprisingly effective strategy on the server. This is enabled by the fact that it's very tedious to manually sell things with many clicks through the auction house but easier to sell at lower price in bulk.
The nice part of mostly trading is that I don't really have a base, I only have a few shulker boxes of inventory that I can just keep on me and log out or in my ender chest. During the weekend my base did get found and I got killed, but the people were nice enough not to blow up my farm and gave me some totems and diamonds!
I'm going to stop the experiment but it looks realistic to be able to get to a billion dollars in a week or two using this strategy. Would love to a see a youtuber try it out!