Actually Castor Oil would be good too as an extractor and carrier as it is skin softening and readily absorbed by the body.
Thats what I was thinking, and it should be fairly easy for them to make themselves. Although the vaporizers sound good, they are trying to avoid the "dopey" effects. Dams
the vaperizor wont help them avoid the dopey effects. If anything It can compound it because they are getting only the cannabanoids, and not all the tar, carbon monoxide and 100 other chemicals released with burning. However, they will use less for the same effects. More efficient use for inhaling.
For his needs I'd suggest he locate an indica -dominant strain (northern lights, blueberry, shiskaberry, snowbud(akorn, orange skunk x big bud), etc) and harvest after the trichomes have mostly turned. It has more body effect and less head effect, but it tends to induce sleep. Heat activated capsules of dried ground trim are effective too. Seem to be a little less sleepy (but makes me flat-lined). Onset is 1-2 hours and duration is around 10.. With vaping onset is < 10 min and duration is about 2-4 hours.