GET A JOB!
Don't become a crack/heroin-addict that pawns their shit for drug money.
Later on you will feel very guilty for doing so.
But you will feel very proud if you buy weed purely out of money you earned yourself from your job.

If you're really that desperate, don't sell your games, just sell shit you really don't want that's just taking up space like dvds or music.
But most of all, you should really get a job.
If you really can't even hold a job, then just work random gigs you can find. Like, a one day work thing.
I did those.. I moved boxes for this couple and it was only an hour and a half of work and I made 40 bucks.

And don't bullshit yourself, you're not selling video games to improve your life, you're selling video games to fix your addiction by getting more weed which is just as bad as playing video games all day.