BBQ chicken from smoker? To sauce or not to sauce

We've got a concession trailer and sell pulled pork, hot dogs, chicken strips etc.  I want to offer BBQ chicken as well, but had a question.  I'm using a cookshack smoker for my pork, and have smoked chicken on occasion for family, but always with nothing but a rub.  If I'm wanting to offer a "BBQ" chicken, should I add sauce to the chicken before smoking?  I know that grilling it would burn the sauce, but I've not tried coating the chicken with sauce before smoking.  Any suggestions?  We'd smoke the chicken, then hold hot in a Cambro in the trailer.

Thanks!