1) You CAN DEFINITELY smoke daily for $100/month WITHOUT selling. If you live in an area where a gram is $20 then that's a different story. A bong is a pretty conservative way of smoking.

2) The comments he's making sound like he is definitely self-medicating. You say it's not because he does it regardless of what he's doing or how he's feeling....well yea that's because mental illness can be 24/7.

3) "He'll say it's just weed" - to an extent this is true. Prescription pills can have a lot worse side effects, be more expensive, addictive, etc. However, they can also do a hell of a lot more positive than weed depending on the situation considering weed is just a band aid and doesn't get to the route of the issue. Therapy could also be worth looking into.

4) I don't think there is a correlation between stoners and being bad with money, I think in general most people just suck with money

5) "Sounds like something a cliche addict would say" Lol I mean the only other answer would have been no which is also what an addict would say...lose-lose trick question?

Depending on how life goes, people will switch dosage accordingly. I agree it's unlikely he's going to just stop but at the same time he's only 25, plenty of time for change. It really just boils down to enjoying the sober life which is something he has to work towards (easier said than done).

Also, your best bet at moderation is getting him to start later in the day and avoid the wake n bake. Once you start toking you won't stop until bed to avoid burning out. Maybe scale out a specific amount for each day if you're worried about the money aspect of it, easy to make it a fixed cost and not a variable one.