It is hard. I know how you feel. My brother was kind of like that. I have a 21 yr old and can see it is difficult as a parent sometimes with adult children.
Here are my suggestions.
1. Dont' cater to him at all. He can do his own laundry, clean his own room, bathroom, whatever.
2. What does he drive and who pays for that? I would end any help in that area--dont' work, you dont' really need that car, do ya? ;-p
3. Cell phone? Who pays for that? Dont' really need that either. House phone? Computer? Don't need those either unless he is willing to pay for that service (I would make an exception and take messages for job interviews being lined up)
4. I would have a talk with him and explain that starting in 2 months (that should be enough time to at least get a job at mcdonalds if nothing else) he needs to have income because....
a. you will be charging rent-at least the money needed to cover his food bills/electricty for lights and hot water.
b. you will be expecting him to keep his areas clean.
c. you will be expecting some physical help around the house--painting, cleaning, yard work, whatever.
Nothing comes free at all except the air you breathe and welp you are an adult so it is time to act like it.
You may also want to consider house rules-not money issue related.
When our 21 yr old lived here, he had to be home at 11 p.m. or be extremely quiet entering. My dh is a light sleeper and has to get up for work in the morning so he insisted on that. Our son also had to keep his area clean (but mine is neat freak so that was not an issue).
He moved out for the freedom of having company whenver he wanted--even if it was guys playing videos at 2 a.m. He comes home all the time since he lives nearby, but he prefers paying rent and having that freedom to being here full time. ;-)
I would look at what is making it easy for him to not work and be so comfortable. I would also ask him if he is depressed or afraid of something. Some people find it difficult to socialize or attempt job interviews. If that is the case he can start seeing a therapist that could help him overcome that, set goals, and move forward in life.
Good luck