Tips For Architectural AR

I’m brand new here looking for some tips on how to do image target based AR for architectural visualization. What I’m trying to do is all interior. The image is attached are not using the kitchen model that I want to use eventually but I was just experimenting with a dot GLB file that I had on hand of a little go kart. As you can see in the two go Kart pictures they are not oriented the same in relation to the image target. Another problem I’m having is scale. The image target is supposed to be the size of an 8 1/2 by 11 piece of paper. The go Kart should be about 6 feet long not 6 inches long.