Just curious but how much would cost most expensive items?

for example have anyone ever droped 4LP top tier legendary? like for example the amulet with +1 all skills or the void gloves from elder i know they are far more rarer than mirror of kalandra in path of exile surely somethin like that would have tens of bilions as minimum in gold? is there any limit on auction house? is there tax for adding items too or wut

I want to say that the max gold you can have is ~2 billion, there’s no gold tax but the favour cost fulfils that function.

I’d imagine a 4lp Ravenous Void or Red Ring of Altara (the 2 rarest items in the game) would attract the highest price.

That is correct. The max value should be 2,147,483,647, which is the max value of an int32 variable. But it’s possible that it will be changed with 1.1 and the variable type could be increased. At the very least, I expect that they have at least fixed the rollover bug, where the variable rolls over to 0 if you pass the limit.

As for the gold value of the most expensive items, I expect the market will dictate the value. If you have a 4LP ring and there’s one for sale for 2 billion, you might sell it instead for 1.9. And if another drops somewhere, they might sell it for less.
So there’s really no prediction how much it will cost, since it will depend on how many are available in the market. Rarity is offset by the number of players. So if an item has a 1 in 100k chance to drop but there are 1 million active players in MG, you could expect to have roughly 10. That doesn’t mean I expect there to be 4LP rings in the first few months, but given enough players you can expect to see some over time.