Knowing that Josh Jacobs is listed as questionable, is it a better play to start Devin Singletary over Jacobs in this week? My waiver wire is pretty scarce for other options. 
Do you need floor or ceiling?
Singletary has a floor of about 3 and a ceiling around 10-12.
Jacobs has a floor of 0 and a ceiling of 20+.
I’d go for the floor when ahead in the projections, and for the ceiling if I’m behind.
Jacobs, agree with ZakHH without knowing scoring.
I agree with the consensus, I don’t foresee Jacoba having a monster game. Although I do see him scoring more than Singletary.
I think OP asked about a week 4 start.
In week 5, Jacobs should be a no-brainer., as long as his injury status isn’t downgraded.