The following is a guide of observations of customer patterns after my third round of playing the game. Most important is the "Suggested Pricing" which could help any new player make or break the weekly debt payments. I've also added other observations such as the time of the day customers usually come in and my best guess as to what each customer's budget.

First, few quick tips for the new players:

• Try to complete the first Dungeon, The Hall of Trials, in your first couple days. The quicker you complete it the quicker you move on to the better loot.
  
• Always invest in food to bring with you on your Dungeon Delves, theres nothing worse than getting all the way to the boss and not having any food.
  
• Don't get too greedy during your first week. 10,000pix is alot easier to gain than you think and the more customers that leave happy early on, the more customers there will be avaliable later on to buy your more expensive loot.
  
• Remember to keep in mind your customer's budgets. If all you're stocking is expensive treasures during the first week and all your customers have a budget below 5,000 then you wont make alot of sales.
  
• When in doubt, mark it down. If your not sure what a customer's pricing goal and budget is and dont want to lose your exp combo stay at 105% mark up and your usually safe.

And thats it from me, now for the guide.
Enjoy the Advice!

There are 4 basic townfolk that make up a majority of your average patronage at your shop, these customers will be with you from Day 1 to the time you decide to quit:

Little Girl
Budget: Day 1~600 - Day 31~20,000
Suggested Pricing: 105%-112%
Shortage Objects (Red): 250%-255%
When Selling to You: 51% - 55%
Preferred Items: Clothes, Jewlery, Hats, Sweets, Books
Time: Morning-Afternoon
Tips: Keeping a Sweet as a window object increses (or the amount of) Little Girls enter your store

Young Man
Budget: Day 1~ 1,500 - Day 31~220,000
Suggested Pricing: 120%-126%
Shortage Objects (Red): 255%-265%
When Selling to You: 41%-48%
Preferred Items: Weapons, Armor, Food
Time: Noon - Night
Tips: One of the more flexible customers, if your selling a large ticket item you may be able to haggle him to a low 130% number

Mother
One of the pickiest and hardest customers to predict but this is what I use
Budget: Day 1~3,000 - Day 31~150,000
Suggested Pricing: 110%-115%
Shoratge Objects (Red): 240%-270%
When Sell to You: 50% - 54%
Preferred Items: Clothes, Hats, Jewlery, Food, Treasure
Time: Noon-Night
Tips:Of all the customers, she is the one most likely to haggle just to haggle. Even if an item has no markup she may haggle for a less than 1% discount

Old Man
One of the more mysterious customers, very hard to pin down his wallet size
Budget: Day 1~ 1,200 - Day 31~500,000
Suggested Pricing:108%-115%
Shortage Objects (Red):240%-255%
When Selling to You:49%-51%
Preferred Items: Treasure, Medicine, Food, Clothes, Books
Time: Morning - Afternoon
Tips: Has a tendency to request an order 2-3 treasures keep the budget in mind, he often CANNOT pay for 2-3 high end items for the first 2-3 weeks but ends up as one of the wealthier customers during your last week and after,

The following is the list of the unique customers which do not become Adventures-for-Hire for you:

Guild Master
Budget: Day 1~ 2,000 - Day 31~250,000
Suggested Pricing: 125%-130%
Shortage Objects (Red): 260%-270%
When Selling to You: 42%-48%
Prefered Items: Furniture, Food, Treasures, Ingredients
Time: Morning to Night
Tips: Keeping a neutral enviroment increases the chances he will drop by

Alouette
Budget: ??? Likely near or above a million
Suggested Pricing: 139%-149%
Shortage Objects (Red): 270%-285%
When Selling to You: 29%-35%
Prefered Items: Gaudy classed items~ Rings, Treasures, Bracelets, Charms
Time: Morning - Evening
Tips: Her "Just RIght" Heart bonus is around 105%-108% but is always willing to go up near 150% When trying to attract her make sure the window display has at least one "Expensive" item (this will not guarantee she will buy the item, only get her into your shop)

Prime
Budget: Day 7~100,000 - Day 31~ 240,000
Suggested Pricing: 103%-105%
Shortage Objects (Red): 220%-250%
When Selling to You: N/A
Prefered Items: Weapons, Armor, Ingredients
Time: Noon - Night
Tips: If, for whatever reason, your trying to attract Prime to your store then she has a prefrence for a Dark Atmosphere

Euria
An event to make her appear happens once Recette reachs 100,000pix in the Town Square
Budget: N/A, She only sells
Suggested Pricing: N/A
Shortage Objects (Red): N/A
When Selling to You: 210%+
Prefered Items: Rings, Treasures, Bracelets
Time: Morning - Night
Tips: Warning, her original sale price is default at 500% but she is usually willing to drop to 220% or so and a little lower if the item is not avaliable in stores at any time. All items she sells are overpriced and not worth the hassle unless you are looking to fill the encyclopedia or gain a Fusion ingridient.

Adventurers are characters in the game that are for hire to delve through dungeons for you and have small side storylines. The more you use an Adventurer, the more likely you are to see them in your store. Because of the differing times players will get different Adventurers its hard to pin down their exact Budget size, so keep that in mind. To keep back as many spoilers as possible, i've decided not to mention how to obtain them.

Louie
Budget: Day 1~1,000 - Day 31~25,000
Suggested Pricing: 106%-110%
Shortage Objects (Red): 220%-240%
When Selling to You: 59% - 70%
Preferred Items: Food, Weapons, Scarves, Shields
Time: Morning-Night
Tips: Louie's Suggested Pricing range seems to be tied into the amount you play with him, it is possible to get him to regularly accept 115%-125% later in the game but he does not usually sell below 55% without a complaint

Caillou
Budget: 3,000 - Day 31~400,000
Suggested Pricing: 118%-123%
Shortage Objects (Red): 250%-255%
When Selling to You: 50% - 55%
Preferred Items: Staves, Robes, Books, Rings, Ingredients
Time: Morning-Night
Tips: Calliou is one of the only customer to buy Common Ingredients such as slime or bat wings and is attracted to Dark Enviorments or Books in the window display.

Charme
Budget: 2,500 - Day 31~400,000
Suggested Pricing: 118%-120%
Shortage Objects (Red): 250%-255%
When Selling to You: 51% - 55%
Preferred Items: Daggers, Treasures, Shoes, Rings
Time: Noon-Night
Tips: Charme can easily be sold to by sticking to 120% and usually buys the more expensive items in the store (if in her budget) to attract her more often either use her more in adventures and/or place the "Boozes of the World" in the Window display.

Nagi
Budget: 6,000 - Day 31~350,000
Suggested Pricing: 112%-119%
Shortage Objects (Red): 245%-255%
When Selling to You: 51% - 55%
Preferred Items: Spears, Armor, Books, Food, Ingredients
Time: Morning-Afternoon
Tips: Nagi's purchase patterns are odd, if there are no spears or armor around she seems to choose food or random ingredients

Arma
Budget: 2,000 - Day 31~2,000,000
Suggested Pricing: 129%-132%
Shortage Objects (Red): 250%-265%
When Selling to You: 51% - 55%
Preferred Items: Books, Food, Ingredients, Armor
Time: Morning-Night
Tips: Arma, being one of the few customers to buy near or above 130% is a valuable customer and is usually very laid back but if angered she often disappears for days on end.

Elan
Budget: 8,000 - Day 31~55,000
Suggested Pricing: 105%-112%
Shortage Objects (Red): 220%-240%
When Selling to You: 59% - 70%
Preferred Items: Books, Food, Gaunlets
Time: Morning-Night
Tips: Elan can sometimes buy items at 120%-130% but many times will first say he is too broke for that. To keep your sale combo and customer popularity up I suggest selling to him no higher than 112%

Tielle
Budget: Week 4: 90,000
Suggested Pricing: 106%-110%
Shortage Objects (Red): 220%-240%
When Selling to You: 59% - 70%
Preferred Items: Bows, Clothes, Books, Rings, Hats
Time: Morning-Night
Tips: I did not get Tielle until the last week so Im not sure what her earlier game budget is

Griff
Budget: Post-Game: 4,000,000
Suggested Pricing: 105%-110%
Shortage Objects (Red): 220%-240%
When Selling to You: 55% - 60%
Preferred Items: Gauntlets, Capes, Rings, Books
Time: Afternoon-Night
Tips: I also did not get Griff until late in the game and am unsure what his budget is. He has a rash personality and does not like to haggle.

Over the years, I've gotten a lot of comments about successes of making more than suggested in the guide. Just to note, this guide was written to help folks get to the finish in the safest way possible, utilizing thin and secure margins. Yes, in most cases, you can press for a higher percentage of return, but at the risk of losing a transaction that may break your streak or end up forcing you into an accidental game end (I have had a game end after being short by like $11).