Reach the indicated level of friendship with the corresponding character to unlock their special friendship ability:
Alex (screen name "LiberatedWoman")
Method: Look for the personal ad from "LiberatedWoman" in the "Women seeking men" section of the "www.craplist.net" website. Alex is somewhat of a self-centered, spoiled rotten rich girl. She will compliment Niko for wearing expensive clothing and driving expensive cars. She will also write about her exploits with Niko in her blog at "www.blogsnobs.org". Reach 80% friendship with her.
Special ability: 50% off at all clothing stores.
Method: Take him bowling, drinking, eating, strip clubs, shows, helicopter tours, and boating to reach 70% friendship.
Special ability (Chopper Ride): Call Brucie, and he will fly his helicopter to you. This allows you to fast travel to various portions of the city.
Carmen (screen name "SoboHoe")
Special ability (Health Boost): Restores Niko's health over the phone. She will call Niko every chance she gets.
Method: Take him to strip clubs, eating, drinking, shows, and bowling to reach 60% friendship.
Special ability (Extra Help): Call Dwayne to have a car full of gang members follow you.
Kiki (screen name "LawChick")
Method: Date LawChick via "www.love-meet.net" through the in-game internet. Take her out a few times to reach 75% friendship. When dropping her off, select the "Try your luck" option. Afterwards, she will call you and say she can clear the feds.
Special ability (Remove Up to 3 Wanted Stars): Call her on your cell phone, and select "Clear wanted levels".
Method: Take him to darts, shows, pool, drinking, eating, and strip clubs to reach 60% friendship.
Special ability (Discount Guns): Call Little Jacob, and he will drive out a car full of guns for you to buy.
Method: Take him to strip clubs, shows, darts, drinking, bowling, pool to reach 75% friendship.
Special ability (Boom?): Call Packie, and he will make a car bomb for you.
Method: Take him to bowling, darts, drinking, eating, pool, shows, and the strip club to reach 60% friendship.
Special ability (Free Ride): Call Roman, and he will send a free cab.
Method: Successfully complete all 30 of his vehicle thefts.
Special ability: The South Bohan garage will now offer money for any vehicle you deliver. The better the condition, the more money you will earn.