When arriving in a new town, the Player Characters (PCs) will invariably want to visit the shops. While ultimately it's up to the GM to determine what type of items are available, the below provides for a response to the PC's specific requests.

Purchasing Items

All shops have a Mercantile rank that relates to a shop owner's experience and success in their industry. The rank of a particular shop is up to the GM's discretion, but as a general rule carts and temporary stalls are ranks 1-3, permanent shops ranks 4-6, expert craftsman and extremely experienced specialists rank 7+. This is just a general guideline, however, and it is definitely possible to have the old traveling tinker with a Mercantile rank of 8 or the inexperienced Blacksmith with a rank of 2, even with his own shop.

When looking for a specific item, the GM makes a Mercantile check for the shop (use shop owner's Wisdom Modifier [WISM]) and compare it to the chart below. If the check meets or exceeds the DC for the rarity of the item sought, roll for the quantity of item available. If the Mercantile check exceeds the DC by 10 or more, increase the available quantity by 1.

⇑ Lower Higher ⇓	Rarity of Item	Mercantile DC	Quantity*
	Very Common	5	1d4
	Common	10	1d3
	Uncommon	20	1d2
	Rare	30	1
	Very Rare	40	1
	*If DC exceeded by 10 or more, gain +1 Quantity.

As always, an item's availability is ultimately up to the GMs discretion, and when not appropriate to the campaign or the locale, the GM may rule that items are unavailable regardless of the check. Similarly, the rarity of an item might increase or decrease based on the setting and location of the shop. Generally speaking, if an item is not produced locally, its rarity should be increased by 1 level (or more).

Shop Sizes

The size of the shop determines the number of chances of an item being available and increases the rate at which inventory will be replenished. Gain a number of Mercantile checks for each item based on the size of the shop. If more than one check succeeds, simply add to the quantity of the item available.

Size of Shop	Number of Mercantile Checks	Rate of Inventory Replenishment
Small	1	6d6 days
Medium	2	5d6 days
Large	3	4d6 days

Types of Shops

Most shops are Trade Shops dealing in all items of an individual trade, such as a Weaponsmith dealing in most weapons or an Alchemist shop dealing in alchemical goods and components. Some shops are General Stores containing a large variety of goods, but usually only those of mundane quality and common rarity. Specialty shops are those dedicated to a very specific merchandise. Masterwork craftsman (using a specific technique, metal type, or weapon group) and some temples (selling potions and rituals specific to a deity's domain) may have shops such as these. The type of shop can modify the effective rarity of items, the frequency of replenishment, and the chance of finding an item.

Type of Shop	Modifier
General Store	Treat rarity as 1 degree higher; Increase Rate of Refresh by 2d6 days.
Trade Shop (most shops)	None
Specialty Shop	Treat rarity as 1 degree lower; Treat shop size as 1 larger (for number of checks and replenishment).

Selling Items

When attempting to sell items to a Shop, the GM makes a Mercantile check (based on the shop's Mercantile Rank) and determines, based on the items rarity, whether or not the shop is willing to purchase the item. If the check succeeds, roll for the quantity of item the shop is willing to purchase. If the check exceeds the DC by 10 or more, increase the purchase limit by 1. Additionally, the seller may make a Mercantile Check [DC 30] to convince the shop to purchase an additional quantity (provided the shop is willing to purchase at least one).

⇑ Lower Higher ⇓	Rarity of Item	Mercantile DC	Quantity*
	Very Common	5	1d4
	Common	10	1d3
	Uncommon	20	1d2
	Rare	30	1
	Very Rare	40	1
	*If DC exceeded by 10 or more, gain +1 Quantity.

The rarity of the item a shop is willing to purchase and the percentage value they will give you on a sale is dependent on the type of shop. Additionally, the size and rank of the shop limits the gold value (gp) that they can afford.

Type of Shop	Rarity willing to Purchase*	Sale Value
General Store	Common and lower	90%
Trade Shop	Uncommon and lower	70%
Specialty Shop	Rare and lower	50%
*Shops of Mercantile Rank 6 or higher will purchase items of Rarity 1 higher.

Size of Shop	Max GP Value
Small	100gp x Mercantile Rank
Medium	500gp x Mercantile Rank
Large	5,000gp x Mercantile Rank

As usual, these are just basic guidelines and the ultimate decisions about whether an item can be sold and its sell value are determined by the GM.