Guild Wars 2

Am I allowed to use free accounts as mules to carry stuff for my main in order to put my investments in and use as storage?

Considering the restrictions on free to play accounts I don’t think you will be able to. You can send items to them but you won’t be able to send them back from the free account. F2P accounts can’t send gold or items in mail or use guild banks.

Here is a list of restrictions for various account types including F2P

https://help.guildwars2.com/entries/95982157

You can not trade items from a P4F account, only to one. So not a good idea.

ok thank you