Hi and greetings of the day.
As a professional model and render artist I have also contributed to many of the examples you and many people search & download. Its part of my daily work, bread & butter kind of thing.
I have been creating virtual 3 D worlds based on architects' drawings, designs, ideas, sketches, etc. for over two decades. Along the way I also have accumulated huge collections of models for entourage and they can be used without any additional charges in all my works. Plants & trees, vehicles, furniture and fixtures, lights, toys & decorative items, et all. You will definitely have a large choice in those selections.
The essence of such online jobs is timely communications with prompt responses that keep both the sides equally excited and occupied. I hope your side would be so because I am always available as a freelance artist and usually respond quickly within an hour unless busy in some other job/work.
I sincerely hope this is going to be as fruitful as it is posted to look like.
Oh, just saw that you have mentioned Rhino and I work mainly with max because that gives you much better & faster results. The world standard in visualization.
Thanks and regards.
Umesh Raut