Before shelling out money for anything, she should ask herself, "Can I achieve the same goal for less money?" I was able to live in LA for four years as a grad student, spending approx. $500 a month. I had 3 roommates in a 2-bedroom, drove a used car, and purchased most of my groceries at the 99 cent store.
As others have mentioned, I think her primary focus should be building various income streams, though I don't think she necessarily has to wait tables or be a cashier to do so. I think she might be able to use her training and talents to build income.
For example, she could get a side hustle. If she's a professionally trained musician, post an ad on Craiglist offering to teach her instrument. Look on Craiglist and the other job hunting websites for music schools hiring teachers to teach little kids on weekends. I've found that they're usually not too picky (I was able to get a job as a piano teacher with a Grade 10 Royal Conservatory of Music certificate). Pay was kind of crappy, but it was better than nothing, and after the parents get to know you, you can switch them over to private lessons and charge higher rates. The music school job was just to build my resume.
If your sister is a native English speaker with good written English skills, she can also offer herself on Craigslist as a college tutor. There are many international students who hire tutors to edit their college essays and tutor them on their homework so that they can pass their courses. They're wealthy and can pay a good rate for your services.
Weddings are another option (or any other big events that might need someone with your sister's talents). Build a website and advertise her services.
