One of the areas where there is considerable diversity in genre fiction is how superheros and people who are, or are waging war with supernatural or alien forces come up with money to fund their operations and support themselves.
Some heros, like Superman (reporter), Spiderman (photojournalist) and Daredevil (small firm lawyer), are middle class guys who work day jobs and fight crime as a hobby, sometimes assisted a little in their day jobs by their superpowers, but not inordinately so. Most of the leading characters in the TV series "Heroes" likewise have ordinary day jobs from waitress, to Japanese salaryman, to cop, to professor, to carnie, to support themselves, or are kids supported by their parents.
Some heros, like Batman (CEO of the corporate empire his parents built), have ample inherited wealth. Tony Stark aka Iron Man, in contrast, is a self-made millionaire, or at least, at any rate, has earned much of his wealth regardless of what he has inherited.
In the Japanese manga Tiger and Bunny, and a recent American animated superhero television series whose name escapes me, the government funds a league of superheros. The Avengers seem to operate on this model as well.
Some have modest income jobs subsidized by modest family money. The witches in the TV series "Charmed" (museum curator, restaurant manager and odd job worker) have day jobs, but wouldn't have been able to afford to live in San Francisco had they not inherited their house from their grandmother.
Younger heros, like Buffy the Vampire Slayer or the heroine of Meg Cabot's Mediator series, live with their reasonably affluent parents who pay their bills.
At the bottom of the supernatural social class scale are the ghost busting, demon slaying pair of brothers from the TV series "Supernatural" secure much of their funding through various fraudulent cons. Also scraping the bottom are the grim reapers in the TV series "Dead Like Me", who live off property pilphered from people whom authorities have not yet discovered are dead, work days jobs as office temps and meter maids, for example, and eat at a nasty diner.
Some supernaturals are openly paid for using their powers. The warlock of the Dresden files is a self-employed consultant who is paid for using his powers. The supernaturals in the Japanese manga series Raetsu work for an exorcism agency. One of the witches in the "True Blood" series does exorcisms for cash. A woman with the power to speak with the dead in one of Kelly Armstrong's books does a traveling show in which she claims to be able to speak to the dead for members of the audience although most of those encounters are fake.
Professor Xavier of the X-Men appears to finance his operations with wealth derived from use of the powers that he and his students have at their disposal.
In Kelly Armstong's contemporary supernatural world, most supernaturals are employed by propserous Prussian style big business welfare states called Cabals, run by ruthless sorcerers who bridge the gap between ruthless executives and organized criminals. Another few run a law firm and private investigator's office specializing in supernatural matters. One of the werewolves is an anthropology professor, one of the half-demons is a tabaloid reporter.
Vampires seem to have a knack for accumulating wealth. The Twilight Vampires live off trust funds that have grown for centuries with the powers of compound interest, in addition to one income as an ER doctor, although the nomadic vampires tend to be less affluent. The Vampires of the TV series "True Blood" and the "Vampire Diaries" TV series seem to favor small and medium sized businesses and tend to own property, although typically only residences. The vampires of Anne Rice's novels also tend to have rather more luxurious lives.