Do some 3D Modelling

I need a grave designed. This is a grave for a couple laid to rest together. I have a photo that resembles what I am after which can be used as guide, as well as a description that details the specifics of what I want altered and how the design should differ from the photo. The purpose of the deliverable is to be used as blueprint when crafting the actual grave. PHOTO: Please see attachment. DESCRIPTION: The design should be similar to the photo with the following changes: 1) Little house on top of the angled head to be removed entirely (i.e. including the angel and pillars) 2) Make the gradient of the angled head less steep. 3) All stones to be solid blocks with smooth rounded ends (i.e. not made from panels) 4) The base is to be 2-tiered as in the picture, with the upper tier slightly smaller and of a contrasting colour. 5) The angled head should have a different coloured stone layered into the face (i.e. first chisel out an inner region of the face to make room for the layered stone, leaving a small gap all around). This stone will have all the writings e.t.c. on it. 6) Instead of the gap containing the flowers at the bottom, just have it slightly chiseled out and make room for a brass plate that will be layered in. This brass plate will have the names (husband + wife) of those laid to rest there.