So first to remind you that in expedition you lose roughly about 4 points of durability per item per run, which is actually very much, so running an expedition for making experience is actually expensive. Those who don't mind to pay the repair for the sake of experience - no problem, but most people should be careful. So this brings me to the topic I want to share with you:
G1's micro lazy income from expeditions
I've put 5 quite naked high level mercs into an expedition (60 battles) and given them I think just +0 divine weapon (which will be dismantled when durab = 0 so I get most of the money back for them in elements). There is a pirate and spartan on front row which I never use. A second oracle which I had made long ago for tbs which i also dont use sitting on the 2nd row and in the 3rd row an arty (I had made for the debuff), a class D gunner (backup for PVE if i need) and a 2nd monk. Spartan and arty are around level 130. Pirate is around 120. Oracle and monk are 113 (if i would need them i can put nix on em).
So I have put life pots on spartan (the leader) and 150 class 3 mana pots on all mercs. I have experimented sending this party to all kinds of skirmishes in expedition but basically the sweet spot is the Ruined Labyrinth.
You can JP literally whatever in the loot window and it gives you roughly about 2 mil gold and you just send them right back without looking / checking items or whatever.
So lets say you send them 1 time in the morning before work, 1 time before you have dinner and 1 time before you go to sleep, that makes it 3 times per day, which makes it 90 times per month. 90 times x 2 mil income per run is 180 mil gold per month. Which I know is a relatively silly number for high level people, but it comes from just 3 clicks per day. Those people who have access to the game during most of the day can easily send 5-6 times, which then doubles the income to around 360 mil per month.