Leveling spots I can help you out with, but money, well, that's not an easy information to give you. Any "sell x item to earn money" tip has an expiration date attached to it as soon as it goes up on the forums. People tend to flock to them immediately. That's why you probably feel those very tips are outdated, so keep that in mind. Generally, it's far easier to sell consumables and quest related items than gears. There are exceptions to that like "go-to weapons" such as Carga mace, Big Crossbow, Hurricane Fury, and so on which are guaranteed sell. Also, it's profitable to sell certain Pet eggs such as Incubus, Succubus, Loli Ruri, Imp, Whisper, Marionette, and Tikibalang so if you ever get tames for them, it's worth your time to try capturing them. If you're card hunting, try to go for those not available on OCA or MCA, because OCAs are flooded in the market. iRO has many unique NPCs who trade fairly useless item into fairly marketable items. You should become familiar with NPCs like Ben Recycle, Grandma Boxter, Eat Gear, and Merry Badger.
For early levels, I think it's market-safe to gather consumables. I will list every marketable consumable items that I can think of, feel free to cross-reference your loot with Ctrl+F and your loot name in this thread. They include leveling aides like Sticky Webfoot, Maneater Blossom, Huge Leaf, Fine Sand, Blank Card, High Efficiency Battle Manual, Battle Manual x3, Job Manual, Mercenary Scroll 10(this is a cash item and can only be sold to those with buy shops), Amulets, Bloody Branches, and Dead Branches, Hairstyle and dye items like Detrimindexta, Counteragent, Mixture, Daenggie, Short Daenggie, Black Hair, Glossy Hair, and Golden Hair, upgrade related items such as Eluniums, Oridecons(combined from Rough versions), Enriched Eluniums and Oridecons, Rough/Pure Energy Crystals, Sea God's Anger, and Safe to X Certifications, SP-recovery items such as Declicious Jelly, Iris, Mora Mandarin, Red Prickly Fruit, Strawberries, Unripe Yggs, Ygg seed and Ygg Berries, Speed items such as Enrich Celermine Juice, Guarana Candy, and Speed Potions, potting mats(but not pots themselves because herbs make more money)-such as White / Blue Herb, and Immortal Heart, Mora daily quest items like Insect Feeler, Skel-Bone, Orcish Voucher, and Scale Shell, Sage consumables like Red / Yellow Gemstones, Crystal Blue, Red Blood, Wind of Verture, Fire/Water/Wind Elemental Converter, and Scorpion Tail, Rainbow Shell, and Snail Shells, and general WoE consumables like WoE White/Blue/Violet, Glistening Coat(and its key material Heart of Mermaid), Alcohol, Bottle Grenade, Acid Bottle and its materials Poison Spore, Fabric, Stem, and Immortal Heart, Rune materials like Light Granule, Mystic Rough Runestones, Round Shells and Destroyed Armor, Poison Bottles and its materials like Venom Canine, Cactus Needles, Bee Stings, and Karvodailnirol.
You may also test your luck at enchantment to make your gear valuable, there are various enchant NPCs like Prontera Apprentice Craftsman, Eden Dark Luhir, Eden RWC Enchanter, Malangdo Mayomayo, Lighthalzen Sewer Sorcerer, and Glast Heim Hugin enchants are worthwhile.
Also you may turn your gear a costume version of it from NPCs Alora, Expert Palt, Designer Heidam, Aver De Dosh and Lace La Zard, Mora Artifact Crafter. Some of these are enchantable to stack stats onto the gears, or have special perks such as extra exp earned. These NPCs require some items which are usually not tradable except for "Attack/mATK/Aspd/Vitality/Heal/SP/HP/Power/Intelligent/Dexterity/Lucky/Critical/HealSkil/Small/Medium/ Stones" which are converted from the said Malangdo costume gears.
One suggestion I see commonly in these types of thread is to get Reset Stones(also known as Magical Stones) converted from Eden Merit Badges. This is a sound advise, BUT! don't buy them from cash shop as there are plenty of ways to make those from scratch. It's a steady sell, but it's an item that will never go up in price unless something crazy is happening with updates that prevent players to earn EMBs. In fact, I remember when Magical Stones used to go upwards 10 mil a pop and OCAs used to go 15 mil a pop. Marriage Covenant and Neuralizers went from 60-70 mil at one point to sub 50 mil zenny in price. These items have steadily declined in price in time, even though there are always needs for them. That's the kinda risk you run when taking advise from these threads.
Now, as far as leveling goes, we have something called the Bounty Boards, usually located nearby tool shops of cities. These are fairly reliable to do until max level. They are used in conjunction to monthly spotlight events which will enhance a set of monsters of certain regions. I feel that the actual monsters to kill depend on playstyles and builds, so I'll leave that to you, since my playstyle isn't exactly orthodox. One popular trick is to crack open Battle or Job Manuals right before turning in quests, as they work for the vast majority of quests in the game. When using something valuable like BMx3, I personally leave one last step to a lot of quests undone, and just warp around finish them after opening the manuals as opposed to hunting monsters. There are times when just grinding monsters on manuals is a good idea such as when you get in on a good party, but the rest of the times, I think it's better to use just to amplify quest rewards. The best time to do story related quests are levels 70-110, any lower levels than that you'd be wasting the quest reward exp, and any higher than that, the rewards are negligible. Here is another post I made in regards to quests. Additionally, since then, we've also had the update for of Sara's Memory daily quest in the New World(Dimensional Space), as well as Eclaige dailies which are all good money and exp.
TLDR; be quick on your feet and constantly survey what max level are hunting for to make money, watch out for newbie traps, and utilize the unique content of this server to get far.
