Do some 3D Modelling

Ok the first picture is a picture of my open van, i am doing some signage a 3d look , that it will look like the van is open and there are some dogs inside but in reality the van will be closed. the second picture is an example. I breed dogs and i am trying to promote them. I have added some pictures of my dogs, you could put some which would look suitable to go in the back of the van, you may also put a picture of a lion in as well if feasible. obviously the dogs would need to be cut out and put in the back of the van to give the best look. which could be printed out and out on the van.