Graves not in a cemetery

In Australia (and I imaging in the US) there are often graves on private property (i.e. not in a formal cemetey). We call them lonely graves. Looking at EE 5.13 and 5.14 there is still a cemetery name listed. 5.14 says you should also note the access road. A lot of these lonely graves have NO public access. The owner of the land would have to give you permission to cross several of his fields and/or paddocks to get there. The property sometimes has a name, and it will have a street where it's main entrance is, but this may be no where near the grave. GPS is probably the best way to identify the location, but because GPS gets recalibrated every so often, and because of the risk that the grave will be destroyed by fire, flood or development, I feel that the citation needs to include the date the grave was seen/photographed.

Could someone please show me how to cite this type of grave marker?