Areas of the Keep: Trader/Pawn Shop

This place deals in the sale and resale of most magic items, weapons and armor, as well as trade goods in large quantities like salt, spices, textiles, etc. The proprietor, a middle-aged Aarakocra named Falco Nixon, is something of a wheeler and dealer, but he is a lover of the bargaining game and not a cheat (though the players might disagree). Purchases from adventurers are generally at 50% of the listed cost where given, except for furs and artwork which are bought at 70% of listed cost. His main concern is not simply the value of the thing, but the price he will need to charge to get it to sell to someone else in the Keep (which may be less than list price to begin with) and how long it's likely to sit in his shop before it sells to someone.
He also has a wide variety of items for sale, all of high quality though some may be used and sold for a lower price than the same item would have been if new.
The shop trades briskly in magic weapons, armor and items thanks to the presence of adventurers and the preponderance of caves, temples, tombs and ruins in the area nearby. A hired mercenary guard wearing chain mail and armed with a battle axe and a crossbow sits unobtrusively at a stool near the door, ensuring commerce can proceed without shenanigans. He can bring the rest of the city watch running in 1d4 rounds by blowing his whistle.
Xanathar's describes the process of buying and selling magic items in two different sections of the excellent downtime expansion. Nixon's interactions will be based on that matrix, and the PC can always either accept the given payment/price, or opt not to buy/sell; but entering into a persuasion contest can greatly affect the final offer.

Purchasing from the trader

Nixon always keeps certain magical items in stock - Potions of healing (common, 30gp) and potions of greater healing (uncommon, 150gp). He has a decreasing chance of having any given magical item of a common, uncommon, or rare nature that the PCs may be looking for. Anything more rare than that, he can neither procure for them nor buy from them, for lack of capital and a shortfall of people to sell it to with that kind of money living anywhere near here (minimum of 10,000 for a very rare item, which is  28 years' wages for an average laborer).
Common items: Roll 1D6. on a 3-6, Nixon has the item (67% chance). The cost varies based on his knowledge of demand and how long it will sit on his shelves, but tends to be less than 100gp. 
Uncommon items: Roll 1D6. on a 5-6, Nixon has the item (33% chance). The cost varies widely depending on how in-demand and useful (or useless) the item may be and how hard it will be to sell it to someone else if he doesn't sell it now. Generally these range in price between 100gp and 600gp.
Rare items: Roll a 1D12. on a 12, Nixon may have the item (8% chance) as long as its asking price is less than 10,000gp. He won't trade in items appraised for more than that, because of the impossibility of financing, the lack of anyone else in town with the money to buy something like that, the danger of keeping an item that valuable on premises, and his fear of getting defrauded out of that kind of money. But Confidence Carlysle may be able to acquire, or to move such an item (since Nixon won't buy them from PCs either).
In addition to magical items, weapons and armor, he has a number of other items that may be of interest to the PCs:

• Carved ivory tusk - price 50gp
• Silver cup - price 20gp
• Crystal decanter - price 45gp
• Silver dagger with jeweled scabbard - price 600gp
• Fur-trimmed velour cape - price 75gp
• 3 x blank vellum books - price 20gp ea.
• Gold and silver belt - price 35gp
• Set of tin toy soldiers complete with horses and cannonades - price 40gp
• Used musical instruments, high quality: Lute 12gp, guitar 16gp, viol 8gp, flute 10gp, mandolin 20gp
• Reconditioned heavy 2-shot crossbow +1 with ivory inlays, 18lb - price 680gp. On a successful hit, does double damage (2d10+1), but uses 2 pieces of ammunition on a hit or a miss.

Selling to the trader

Generally the buy price is half of the sell price, though Nixon will pay more for furs and for high quality artwork, both of which he can quickly sell to buyers from the west. Landing on the buy price is not always easy, and haggling over that constitutes a fair price and margin can be an exhausting process (See the persuasion contest above). Generally speaking:
The base value of an item:

• Common: 100gp - Nixon will offer 50gp
• Uncommon: 400gp - Nixon will offer 200gp
• Rare: 4,000gp - Nixon will offer 2000 gp

With consumables (potions and scrolls) valued at half that. As a guideline, potion/scroll spell effects of cantrip through level 2 are considered common, level 3 - level 5 are uncommon, and 6+ is rare.
So that means Nixon will offer 50gp, 200gp or 2,000gp for common, uncommon or rare items he's willing to purchase. PCs can simply take that - OR they can make an opposed persuasion check to potentially get more - or less - than the standard.
If the PC wants to haggle, a persuasion contest will determine the final offer. The PC rolls a CHA (persuasion) check against Nixon (who rolls at +2). 

• If Nixon wins the check, Nixon's final offer will be 20% less (40gp, 160gp, 1600gp).
• If the character wins by 1-5, Nixon will offer 20% more (60gp, 240gp, 2400 gp)
• If the character wins by 6 -10, Nixon will offer 50% more (75gp, 300gp, 3,000gp)
• If the character wins by 11-15, Nixon will double his offer (so 100% of full value)
• If the character wins by more than 15, Nixon will triple his offer (150gp, 600gp, 6,000gp)

Alternative Names

Pawn shop

Parent Location

The Keep on the Borderlands

Owner

Falco Nixon

Characters in Location

• Falco Nixon

Related Report (Primary Locations)

• S1 E20: The Shopping Episode