1. Potion Business [Starting Research] and Energy Potion
Since unlooted money are gone at the end of the day, Vendors/Sales are the best way to power up and sustain our economy (along with quests' rewards and entrance fee). To no one's surprise, potions are the first gateway to our wealth.

Health Potion sells for 10 coins with 5 bottles each, while Energy sells for 15 coins each. During demo you can jack up the price and the adventurers will still buy them despite complaining about the costs, however in the released version they will not purchased the potion at all even if you increase by 1 coin.

You want to jam these potions into every nooks and crannies your starting room. In mine, I've up to 6 potion stands of each type, chests to accompany them, and traps and 3-4 spawners to keep the heroes busy and damaged. The faster the monsters die and regenerate the more money is stored in the chests and therefore more wealthy your heroes will be. You want them to line their up their pockets and keep on purchasing our potions.


Once the stands run out of potions, any hero that linger for too long will get mop up and contribute to our soul tallies -- and since they will be fighting monsters on and off, you can guarantee they'll die happy and won't hurt our rating that badly. In the first few days, you might need to manually time and drop in additional monsters to keep the heroes occupied.

I like sticking potions everywhere I can, in the room with the monsters as well as in the travelling corridors. Generally, you won't see a lot of excess potions at the end of the day.


2. Attack Totem, Respawn Pedestal & Goblin Grill
Respawn Pedestal is a critical part in keeping your heroes alive and happy (for long enough) in this Lotus Hotel. Did you die without purchasing a potion? Here's your second chance.

The Respawn Pedestal repaid its value very quickly once you added other vendors to your dungeon, since if the potions are out, the adventurers might start looking at alternative, which are often more expensive and therefore more profitable for us. Ie. Grill burgers come at 20 coins each.

From my observation, it doesn't seem like the heroes are respawned with full health/energy. Often they'd beeline for potions & burgers right away before carrying on their journey. So you can guarantee the heroes will be buying potion if they're re-spawning. At the beginning with weak monsters, you can chuck the pedestal inside the room. The heroes can re-spawn and resume fighting. Later on, you can move the re-spawning pedestal to a safer spot.

You can also stick some attack totems in the starting room if you find too many heroes are dying to your potion-farming starting room. That'll significantly boost their surviving chance (so they can live to buy the potion).

During mid-games, as you started building more resting areas, you can stick more respawn pedestals down. The more you have around the more heroes you can respawn and therefore keep them paying money to your pocket.


3. Legendary Heroes

I recommend getting these online ASAP as they can be be a reliable income early game as well as gauging your dungeon difficulties. Even if your rating/prestige is not there yet, having the tab available gives you a tangible goal/challenge. Getting the Prestige research will also be a great addition,

Once you've unlocked a hero, you can invite him every day, and every day that he is satisfied with your dungeon he'll give you 100 coins. Even if he doesn't, there's no punishment and you can just re-invite the same guy over the next day.

Higher-level heroes will provided better gold rewards for repeated satisfaction. This also counts toward your research's visitors requirements so sometimes the legendary heroes visiting 3 days in a row can make the research a day or two shorter.

Heroes's Best First-Time Rewards you can look out for are: Prince Tristan's Stature of Tristan (Attack/Defense Totem), Midas Goldenthirst's Chest of Midas (stores 150 coins). Sir Silvermane III's Throne of Silvermane (it's paired really well with Midas's chest. Both are so gold and sparkly) and Thalion's Pedestal of Thalion (Respawn Pedestal unlimited).


4. Camping Spot, Grouping Table
These don't provide you with money but they give the heroes better chance of survivals and therefore more opportunities for them to splurge further down the road. However, this can hinder your souls income if you don't have monsters leveled up far enough, so a good idea might be putting the grouping table after your monsters have greeted the heroes. These will kill off a couple of guys at the beginning for souls as well as stall the groups/creating solo adventurers.

Groups keep everybody alive for way longer, and immediately will boost your rating and sales as they will be purchasing in bulks. Depending on how you structure the dungeon, the groups may be doubling-back, which will only further boost sales, although by late-game where you're working with 40+ people per day, these potions are grills are emptied and clean during their return trip -- making the groups vulnerable to monsters and easy to be farmed for souls.


5. Ancient Spawn
The groups will be mowing down the monsters left and right, so getting a spawner that saves you 10 seconds of spawning is a great deal, especially for rooms designed to farm coins & happiness.


6. Large Healing Well
Large Healing Well -- I've got these much later compared to everything else on this list since they are free and eats up into my potions business. However, if you find the potions running out much faster than you want, these wells are good to give your poor heroes a chance to re-supply. I'd recommend going straight for the large healing well since both types of healing well takes up a 4x4 area but large healing well provided way more substances. Noted: if you want to go to the Large Healing Well directly, go down the Speed Totem Path instead of the Wood Decoration II.

The Research trees for these threes are pretty much the same. I recommend researching Inferno first as there are 2 vendors you can unlock from that list immediately while others only have 1


1. Blacksmith & Large Health Energy Potion Dispenser

Blacksmith & Large Energy Potion Dispenser both can be found in Inferno's research tree. Large Health Potion Dispenser is found in the Underworld's research tree. Blacksmith sells attack buffs to heroes (11 buffs available, 15 coins each). Meanwhile, the large dispensers took 1x2 space but can spare up to 15 potions and work faster compared to the single ones.


2. Enchanter

Can be found in the Forest's research tree. Enchanter sells random buffs to heroes for 25 coins each spell and can sell up to 11 spells -- buffs included defense, attack, speed, etc. I like putting Enchanter and Blacksmith close together as they function similarly.

Other general upgrades you want to target on your research trees whenever you run into them are:

• Soul Trades: You've the options to lock the chests using souls, but I think the better investment for your souls is to spend it on either Soul Trade (9 souls = 350 coins), level up your monsters, or used to unlock realms
  
• More Monsters: Noted, you should unlock all More Monsters upgrade before you researched the Bosses of each Realm. The Bosses counted toward your monster reserve. If you summoned the bosses before hitting your monster cap, you'll be stuck with less monsters than you'd like (I got stuck with 26 during my first run)
  
• More Visitors
  
• Bigger Pockets: If heroes have more money they're likely to purchase more upfront as well as during their trips

Full-playthrough if you're having difficulties on where to start. This was done on Hard difficulties and an 80x80 map.