Share 'Tips for best car rental choice'

I've got a cluster of out of town stuff coming up in July and thought it might make sense to rent a car for a week.  Since going car free 10 years ago I believe I've only had to rent a car twice, so thought I'd see if I could get some tips from folks with more frequent experience.  Would involve travel to southern Wisconsin and over the Missouri border so needs to be unlimited mileage and not lim…