SS,
It sounds like you are offering your son a temporary hand-up, not a hand-out. We all have done that, with both difficult and non-difficult adult kids.
I would have no problem helping a young person get a fresh start, if it seemed like it would really help, and they were holding up their end of the bargain.
Has he looked into renting a room rather than a whole apartment? My D.C. step-son has lived in several of those. Currently, he is renting the top floor of a house in which the owner, a single man, lives. He has a bedroom and bathroom on the top floor, and shares the kitchen downstairs. It seems to be working out well.
Craig's List, and other local message boards, are a good place to find situations like that, which are often much cheaper than an apartment, which works well for a lower-income person to live long-term.
Hope everything works out for your son! Often, a low-paying job will work into a better job, if he is diligent and patient.
Apple