There is one tavern in Waterdeep that is held in deep respect, and not a little fear! The Yawning Portal is run by Durnan, a warrior of inestimable courage, skill and luck. Realising the latter was a commodity perhaps running out, he retired from adventuring, and set up the Yawning Portal. He built the inn on top of the entrance to Undermountain he'd used to make his fortune and fame, and here it still resides: a great well hole descending over 140 feet into the earth...People who wish to adventure into Undermountain are charged 1 gold piece to travel down the shaft, carried in the bottom half of a huge wine barrel. But, and this is a big but, Durnan also charges 1 gold piece to come back UP! And if you haven't got it, well then, you forfeit all your possessions! It's the rule and no one goes against it, for not only is Durnan a more than capable warrior, many of the patrons are his friends, and they are adventurers too! It is seen as a gamble, a bet of fortune against ruin, life against death. The inn is the home of Durnan and his family, and he doesn't like troublemakers who could ruin his business, or harm his kin. Folk who start fights are generally dumped, totally naked, in Undermountain!

The inn has several folk who can help adventurers, and a well used notice board is on one wall, where various jobs are offered, with suitable rewards. Also, you can at least sleep in the 'Portal knowing you won't have your brains sucked out while you rest, which is a feature Undermountain lacks!
Whenever PCs come to the inn, they spend money on sleeping, accomodations, the latest fashions, making offerings for their safe delivery, buying spell components and the like, as well as paying into the city coffers (even adventurers find the tax man a fearsome beast!). To reflect this, each time a character enters the inn they will be "taxed" 50 gp per level. So a 10th level adventurer will lose 500 gp when they enter They Yawning Portal. However all such folk will be automatically fully rested.
Many folk abound in the Yawning Portal: allies who can be hired on to guard your back; clerics to heal wounds (for a price of course); information can even be obtained and THAT is a treasure indeed!

MAJOR NPCS OF THE YAWNING PORTAL

DURNAN

The owner of the inn. An extremely competant, but tolerant warrior. He loathes two things: hobgoblins and those who cause bother in his home. Believed by many to be a "hidden lord" of Waterdeep. His wife, Mhaere (a priestess of Lathander) and his daughter, Tamsil, also work in the inn.

AJELON VELASCOE

An elven wizard, seller of potions and wizardly scrolls. He often hires adventurers to find components for his elixirs. His son, Camrae Velascoe, is a well known Undermountain delver. The elven alchemist is known to be intimately aquainted with Undermountain, he and his wife, Lady Velascoe (from whom he gets takes the second name according to the family custom), were veterans of the halls below, but after almost their entire circle of friends were wiped out, sought safer proffessions.

JEANNE OF THE SCROLLS

A young lady of remarkable wits, Jeanne is a scribe and scholar of some repute. She spends her days in the 'Portal reading parchments brought up from Halaster's Halls. To make a living, she identifies the odd items folk bring back. It is said she had something to do with the strange goings on around Candlekeep and Baldur's Gate recently.

CALEDRIC

An elderly cleric of Tymora, Calderic was a fierce and proud soldier of Cormyr, before a twist of fate saw him turn to the service of Tymora. The twist being that he lost his leg to a beholder's disintegration ray. He has a dispensation to cast ressurection spells on any fallen adventurer, since they are "dicing" with death, Lady Luck doesn't mind this!
Ressurection is costly: the character loses 1 point of Constitution, 10,000 gp and one magic item!
But that is a small price compared to eternal slumber...He can also cast other curative spells, but he only deals with the more desperate (and expensive) cases, other's he leaves to his acolyte, Jocelyn.

KAY-HAN

From far off Kara-Tur, Kay-Han is a warrior between wars, and this doesn't please him. No one seems to know much else about him, save that he loves true blade skill, and he arranges particularly lucrative, and dangerous, missions.

SUI-THIESS THREE COINS

A young elf, this lady has found a good way to make money: she gets the items adventurers need. Sui-Thiess has a small squad of runners that scour Waterdeep for a client's order, so there is no need to wait! A friend of Aurora, the famed merchant, Sui-Thiess is trying to save up enough money to get a spelljamming ship.

MEDUDUKADIZ OF GOND

A gnome...a gnome cleric...a gnome cleric of Gond! Most folk treat this little lady with the same caution they reserve for beholders or the Tarrasque! However, she is a skilled artisan, well capable of repairing almost any item, and she can cast curative magic, and sells potions and clerical scrolls to boot! But she still wonders why she doesn't get as much custom as Caledric and Ajelon....*gnomish sigh*