It looks like it is going ot be very nice.
I agree though you need more ventilation for livestock. I think your going to have to cut some openings, Those things get stupid hot in the summer esp being black and sheep make a lot of moisture breathing.
You dont actually need to drive it around btw. Put a thermometer in it and close it up except your vents wait until about 3pm on a sunny day and go check the temp. You have an RV, what happens it you have just the top vents open and no ac on in the summer? It gets hot lol this is the same concept but black on the outside, no insulation and smaller so worse.
I've been in some of those "fancy' horse trailers in summer and omg it was hot! They had the windows open, the vents and the back door and it was still hot and those were light grey or white. Moving wasnt as bad cause of the airflow thru the windows from going 50-60mph but sitting for any more then 10-15 mins and the temp went up fast.