When you visit the Copper Coronet in the Slums District, you'll meet up with Nalia in need of help. It seems her father's keep, de'Arnise Hold, is under siege by trolls. Head to the keep, rid it of its invaders, and Nalia will offer you the keep (only if you are a Fighter). If you accept the keep, it will provide 500 gp a week which will just appear in the second floor coffers. You can also raise the taxes for your people if you wish, but each time you raise it they will become unhappy. The more unhappy they are, the greater the chance that they will revolt against you and you'll lose control of the keep.

After becoming the keep's owner, upon return to the keep to grab your weekly gold, you will begin receiving quests. The first involves an angry merchant named Tolmas Bendelia. His caravan was attacked by bandits while traveling through your lands and he wants compensation for his damages. I chose to give him the money he asks for (1000 gp) to avoid further conflict. After you pay him off, you have to decide what to do about the bandits that are in your lands. You get a choice of how much money to spend on mercenaries: 500 gp, 250 gp, or just ignore the problem. These choices all affect how much experience you'll receive (and don't forget about keeping your people happy).

Upon your next trip to pick up your weekly gold, you'll be approached by your Captain. He'll tell you that he has caught one of your guards stealing and will recommend executing him. Instead, you can go talk to the thief and find out that he needed to steal for medicine for his wife. You'll have three choices here: execute him, expel him, or forgive him. I chose to forgive him and received a nice experience reward. You can also purchase the medicine to make your people happy.

On your next trip, you'll find a priest of Tempus wanting to start a shop/temple in your keep. If you let him, you'll get a nice experience reward and your people will become happier once again. You will have access to this temple now as well, up on the second floor where the Golem guardians once were.

Sometime after completing the temple quest, you'll be approached by a man who tells you to head back to the keep immediately. You'll have to talk with Lord Roenall (Nalia's ex), who will want you to relinquish the keep to him. Of course, I didn't.

On your next visit, you'll have to decide between two men for your maid to marry. She is in love with a man named Jessup (but he's poor) and the other man, Malvolio, she doesn't love (but he's rich). It seems obvious that you should choose Jessup in order to keep your people happy, so that is what I did. You'll get a nice experience reward, but you'll also need to provide a 500 gp dowry.

You'll have another choice on your next visit... two men claim that the previous keep owner had borrowed money from them and that they want it from you. You'll find that there was no such debt and that the documents were probably forged. You can just threaten them with executions to avoid having to pay them. However, they have a hold over your people, so you'll have to pay either 500 or 1000 gp for them instead.

The next crisis at the keep - your dike has given way and the land has been flooded. Your farmers request that you repair their farms. You can either give 5000 gp, 4000 gp, 3000 gp, 2000 gp, 1000 gp, or nothing. Since money wasn't an object for me, I dished out the 5000 gp to keep everybody happy. After that, however, you still have to spend 2000 gp to fix the dike.

The last problem that you should encounter at the keep is when Lord Roenall invades your lands. Your captain will ask that you go out and stop the invasion. Head out onto the battlefield and attack Roenall. Once he's dead, the battle is over. You'll get 50,000 xp for defending the keep and an additional experience reward for defeating Roenall. If you want, search Roenall's body for some minor equipment, such as a Bastard Sword +1 and Full Plate Mail +1.