I wouldn't rely too much on some income figures floating around. Those who know won't tell and those who talk about don't necessarily know.
More generally, when it comes to modeling it's important to consider a whole fiscal year and compare the annualized income to other jobs. A USD 5000.00 photoshoot sounds nice but if you don't do anything else during a couple of months it's a very low average income and expenses don't wait.
For the average young model, modeling should not be primarily about money. It's far more about a unique life experience, opportuntiies to become independant at a young age, to travel and work abroad, enjoy other cultures, meet interesting people, partying... (maybe that one I shouldn't have mentioned LOL).
Blunier
Edited:
Note:
An average model doesn't get paid USD 5000.00 for s imple photoshoot, that amout in the example above is related to the commercial use of the images (ad campaigns etc.).