In a nutshell, a rotating - categories card offers bonus cash back, usually in the 5 percent range, for particular credit card transactions during a given period of time. (cardratings.com)
Also, there's protection included with particular credit cards; it's always worth checking with the bank. (rocketlawyer.com)
I would notify everyone that you have a policy of particular credit and background standards (actually create a policy, preferably in writing). (biggerpockets.com)