That is a hard one with out seeing the property, but generally the first thing I would do is get a Topo or Ariel map of the farm and adjacent farms. Look for pinch points and funnels where the cover gets thin or pinches down. Another good place to start is inside corners of field edges where the crops and woods meet.
The best thing to do is when you visit the farm to scout, in the evening get set up where you can view the most area of the farm and wait with a good spotting scope and or binocs. As the sun goes down start scanning all areas. Once you locate where deer are, fine tune your search and next time figure out exactly where they are coming out. This should give you a good game plan for evening sits. Also once you know where they are coming out see if there is a way to sneak in 100 yards or so off the field edge in the woods and this could be a good morning spot. Once your season is over with, get in and work the whole place over and know where the bedding spots are. These bedding spots do/can change with season and wind direction. The best thing after studying the topo is spending time down there at dawn or dusk and get to know their movements and yes the Farmer themselves can usually tell you where they see the deer on their farms.
But basically, I think by looking at a topo or ariel map this might be your best tool and answer a lot of questions or at least give you a good start with out even stepping foot on the property. Keeping in mind the wind directions and how the property sits, thinking of access to and from certain stands with certain winds.