We are the one's JC mentioned that have the "Wags" dog trailer. Our dog Ruthie has traveled about 20K miles in the trailer. After watching Brian's build earlier, I have to commend him on pursuing this passion

Although Brian has addressed some concerns here, I will share our experiences and thoughts. Before taking Ruthie, Melanie (sgchick) rode in the trailer for a bit to check for exhaust and noise levels and all seemed fine. My mistake was in letting her out.

I like the idea of a CO detector though. I have an inexpensive wireless indoor/outdoor thermomiter to check for trailer temps from my dash. Movement and airflow are essential in hot weather for lower trailer temps as well as CO buildup at anytime. Our windows are tinted to reduce solar heat and screened to prevent Ruthie from sticking her head out. We do have a solar fan to help in moderate traffic but if we are in heavy traffic in higher temps, we pull over in a shaded area or re route to keep some air flow in the trailer. We also have a cooler which essentially is a cooler filled with ice with a lid fan and port to help cool things down. Mounted on the trailer tongue close to the box is an additional cooler that we use to store dog food, water etc.. Someone even sells a wireless camera and dash screen to view your pets while traveling. We drew the line there though.
Ruthie has been through snow and rain storms but we avoid riding in excessive heat. Common sense must prevail when trailering pets. Speed and driving habits, CO levels, temps, road conditions, etc. should all be taken into account. It's a lot of fun with all the attention and new folks we meet though, weather parked or on the road.
Best wishes to Brian on his new venture and I'm sure that with his love for dogs and attention to detail he will do well.
My vote for a name would be "K9 KOACHES" or "K9 KRUISERS"