Tips & tricks for earning Gold

Some low level suggestions

Pick up floor trash from the first 2 levels of Mileth Crypt and vendor to mundanes in town.
In group hunts, make sure you pick up everything, sell, and pool it all between your group.
Hunt quest items (think low level quests) and sell these as bundles (maybe to higher up players making new characters).
Check spell/skill lists for common/easy to get monster items and keep a stash to sell (Wolf’s Skin, Wolf’s Fur, Wolf’s Lock, Bat’s Wing, Spider’s Silk, Centipede’s Gland, Viper’s Glands etc).
Make a low level priest character, put the items from the first 2 levels of Mileth Crypt into the Mileth altar - you will get experience, can gain Priest only level 41 greaves, and various difficult to make potions only gotten otherwise through Alchemy (think Ainmeal Ioc Deums) to sell to other players.
Hunt Porte Forest - keep all of the Beothaic Deums to sell to other players, small gold drops, and various other potions.
Solo Dubhaim Castle for gold drops/exp - it yields a decent amount.
Rogues should utilise Lockpicking (see Lockpicking in General Info section).
Fiosachd faith - you can pray for gold with good faith here, (see Religion page for more info).

Mid level suggestions

Hunt the Silver Mane - quest item, perhaps sell to higher players making ‘alts’.
Hunt quest items, whatever you’re capable of level wise, Mileth Crypt (stings and bat/great bat wings) are great money for a mid level character).
At insight 30+ start crafting, even if you just gather ores, gems and fibers, you can sell these stacks to other players who are working on their crafting. The coal & ruined fibers also sell at 25k for a stack of 100 (by product of failed gathering).
Work on crafts - you can sell the stacks of items you craft to other players or most of the time vendor to a mundane for gold.
If you choose Herbalism, you can sell the stacks of Herbs to alchemists.
If you choose Alchemy, you can craft the potions and sell to other players.
You can hunt Dark Belts (Marlin’s Request, if you don’t fully complete the quest) and can sell these to other players.
At insight 41-71 you can hunt in Deeper Pravat Cave, hunt here as often as possible and any recipes you find (may need to roll on them in your group, or however you split them), can be sold to Gemcutters who need the uncut and finished gem recipes.
Check spell/skill lists for any mid level monster items and keep a stash to sell (Goblin Skulls, Hobgoblin Skulls, Great Bat’s Wings etc).
Having a Priest character of a faith that can consecrate desirable items, and keep those to sell (Deoch Coral Earrings for example, are good caster earrings, some people may buy these, Gramail boots etc). You can find people dropping items to desecrate for faith in the towns, temples or leaving them in hunting areas.

Higher level suggestions

You may be able to solo some areas well, or have a small group you hunt certain areas like CR with which you can pool/roll on items like rare recipe drops, staves, boss drops etc.
Hunting higher exp and monster items to sell, Mileth Crypt at most levels has an abundance of great monster items to sell.
Check spell/skill lists for any rarer more difficult to get monster items and keep a stash to sell (Wraith’s Blood, Succi Hairs, Marauder Spines etc).
Hunting Fae Wings - these are needed for skills/spells as well as Kas Mines runs. These are a good item to hunt/sell to players.
If you have a high level craft you can begin to charge for 71+/Master+ gear etc.

This is just a suggestion and basic ideas - some people may have more suggestions, if you want me to add anything, feel free to whisper or discord me to add it.

Happy hunting!