From a purely practical perspective and based on experience (and I am not implying it is always a negative experience, but...), things sometimes look very different when you speak to the barn manager/owner in advance and later on when you actually have the horse there.
Make sure you communicate what you expect (and understand what is possible in order to find an acceptable meeting point as things are never 100% perfect) in terms of feed type, quality and quantity, manner of feeding (frequency, timing etc.), turnout (alone or with others, types of turnout partners - shoes/no shoes/age/gender, time of the day, length, space per horse, whatever else), cleaning (both box and the horse's coat and/or hooves after turnout), any other arrangement. Meet the actual person who physically cares for the barn where the horse would be housed and see if you are comfortable with him.
Around here there are barns that are within 5km of each other, but the quality is like night and day. The common amongst them is usually the price and that before you start boarding, things always sound good when speaking to whoever is running the place.