Fallout 3 Reilly's Rangers Walkthrough (Side Quest) - Guide by Carl
To get to this quest requires some patience. You'll have to make some use of the metro system in downtown D.C. This will be much easier to find if you've already made it to GNR plaza, as you can use some of the waypoints there to find it. The goal is to get to Vernon Square. If you have the Dupont Circle waypoint you can go through the metro there. Otherwise, head from Megaton and cross the river to the east, then head south until you find Farragut West Metro Station. Go through there, to find Tenleytown/friendship Metro station.
Look for the area called Metro Junction. In the far east of this area is a door that leads to Vernon Square. Be sure you take the southern of the two exits to Vernon Square. From there, the statesman hotel and our lady of hope hospital are to the south. You should get the Ranger Emergency Frequency on your radio at some point upon entering this area. If you listen to it, you'll be led to Reilly in Underworld, but that's unnecessary. This is a good beacon to let you know you're in the right place, though. Look to the south for the Our Lady of Hope hospital. You'll notice if you listen to the radio broadcast that they are trapped on top of the Statesman Hotel. That area is inaccessible from the ground. Instead, you'll have to go through the Hospital.
You can clear the ground floor if you like. If you don't want to, head to the west once inside. You'll find a staircase leading to the second level. From here, head to the east and you'll find the door to the outside of this level. There's a metal platform to walk across that leads to the Statesman Hotel. You'll have to drop down once across to access the door to Statesman Hotel Mid Level.
Once inside, you'll finally have the mission objective to Locate Reilly's Rangers. Clearly, the goal here is to get to the roof of the building. From here you should be able to clear each floor and navigate to the stairway up each time. There are several levels to be climbed. Stop when you get to the level with the restaurant elevator (it should say statesman hotel mid-level, but several floors do) you want the one with the elevator to the restaurant specifically. On this floor is a ruined hotel room (very large because of the walls being blown out) that has a white bed with a skeleton. Under the skeleton is a holotape titled " a note from Little Moonbeam's Father". Take this for later, as it will help you get Sydney's "Ultra" 10mm Machine Gun should you do the Stealing Independence Quest later. When you finally reach the restaurant near the roof, look in the southwestern storage room for a dead protectron with a fission battery. Look for the exit to the roof from here (in the restaurant, upstairs).
Talk to the Rangers and help them escape. You won't have to go far before they will acknowledge completion of the quest. You'll get the password to the Ranger Compound, where you can go to turn in the quest. You'll have a choice between the unique Minigun Eugene and Ranger Battle Armor. Both are very powerful, so weigh your choices carefully.
If you don't know how to get to Seward Square, the location of the Reilly's Rangers Compound take Anastocia Crossing north of Rivet city and go all the way to the east. This will lead you to the square. From there, the HQ is to the northeast. Use the terminal with the password to get in.
After you get your Reward from Reilly, ask her how things have been going. Comfort her, and try to cheer her up. She'll offer you caps for every map location you can turn in to her. What's more, immediately after initiating the quest, you can talk to her again and she'll pay you for all discovered map locations. That is, if you're weird and took the explorer perk like me, you'll be able to make a lot of money by revealing those map locations. Unfortunately, this isn't very useful at the end game. Players who elect to save Reilly's Rangers earlier in the game will love the free caps they can get occasionaly from going to Reilly.