i think it really depends on the relationship with the dealer.

Long known dealer- Ay foo, gimmie a 40, hook that shit phat ***** (if hes black, nugga)!
- I need weed bitch! break me a 40 now!
Not so known - Ay wassup man, you got a 40 of them trees?
- Ay, know where I can get a 40 of some dank from?

Around here we use, blunt(5) dime twamp(20) half o-z for schwag, half 8th, 8th, quarter, halfy for mid-high grade