After my Dad passed, my Mom sent back to the funeral home, and negotiated exactly what she wanted and paid for it. No issues.
My Mom did the same thing. I will be buried in the same Cemetery as My Mom and Dad, My Grandfather, and Grandmother, and 2 of my Great Grandfathers and Grandmothers on my Dad's side. I have the spots picked and my Wife has agreed that we should go ahead and put up a stone. I figured that She would balk at the suggestion, but did not. Just need to get that done. Nothing fancy in the way of a box or stone. miles