Robe of Useful Items

An uncommon magic  item costs 400gp.  One of the items this could have is 10 gemstones worth 100gp each.  Another item is a silver coffer worth 500gp.    It has 4-16 of these other items.  Possibly it could have 20 gemstones worth 2k gp total.  Can someone help me understand the math behind this??  (Were the designers and editors not paying attention?  The same thing was true of this item back in 2014).

Because its fun. Things do not have to be balanced or faire for the game to be fun for everyone, it also says DM can pick the random patches and can just not pick the massive amount of gold or OR make it a plot point now thieves and bandits have gotten wind of your legendary magical money making robe and are hunting you. This is D&D Math never has to Math here for here there be dragons and mimics.

Also fyi i am 100% not a mimic.

The average value, rolling on the table 4d4 times, of the stuff that has a defined cost or value (so, say you can sell 2 mastiffs for 25 gold each), is slightly over 1500 gp.

I can use my bastion action to make these for 200 gp each.

Just saying...  why have a gaming hall when you can have a sweatshop of robe making?

Or you might get a bunch of pits.  That's the fun part!

Quote from Redbeard197213 >>

The average value, rolling on the table 4d4 times, of the stuff that has a defined cost or value (so, say you can sell 2 mastiffs for 25 gold each), is slightly over 1500 gp.

I can use my bastion action to make these for 200 gp each.

Just saying...  why have a gaming hall when you can have a sweatshop of robe making?

 The DM doesn’t have to roll, the DM can pick what you get. So if you’re making them in your Bastion, the DM can just never pick the items that give you more than 200gp. 

If you allow crafting you need to institute some form of fix with crafting this item. Treasure GP value alone of each patch averages 123gp, crafting this robe has an expected profit of 1,000GP in immediate treasure. This is an infinite money glitch.

Quote from Redbeard197213 >>

I can use my bastion action to make these for 200 gp each.

Isn't the Robe of Useful Items Consumable? Once the last patch is removed, the robe becomes an ordinary garment.

Consumable items take half the time and half the cost, so you should be able to make it for 100gp

10th level Artificers can make two of these every day. Once with their Magic Item Replication, and a second one by Transmuting one of their other items into one.

Where are you going to find one for sale? In my games, magic item shops are extremely rare and won't always carry what you're looking for. Also, what other people said... a good GM can make it complicated for a player trying to take advantage of this.

So on the roll or choice of 76-83 the spell scroll, does the ''your choice'' mean it's the DM's choice or the players choice? Also if it's the players choice on what level, do they also get to pick the spell itself? Or does the DM pick the spell of said level? Or do they go ok all spels of level 3 are x,y,z so I am going to roll a dice and see what lvl 3 spell you got.

Usually whenever a magic item refers to "you" it is referring to the user of the magic item, although in this case a bit confusing.

I am pretty sure the spell is up to the dm's choice because it doesn't mention anything about when you detach this patch and the table is ment exclusively for dm use as stated in the last sentence.

"The DM chooses the patches or determines them randomly by rolling on the following table." 

However I could see a dm slowing a player to choose what spell it contains to make sure it's not useless, maybe just determining the spell level, when they detach it or whenever they find it.

So, as always, it's up to the dm but RAW the dm chooses when creating the item, however they could ask for guidance from the player above table so they don't have to look for a useful spell on top of everything else they have to do.

Alright, thank you.