It really is a good dog trailer FCSPRINGER. The man I got it from made it specifically to field trial out of. I took it to a few trials myself and on a trip to Michegan. As far as ventilation, there are two vents on the top (one front and one back) and each compartment has ventilation holes on the inside so that air can flow throughout the box. The vents on top allow air to circulate throughout the trailer from front to back when moving down the highway. There are also small ventilation holes around the entire rim at the top of the trailer as well as on each door. I actually wanted to put some type of sliding vent on each door so that I could open or close each one individually, depending on the weather and the situation. It doesnt seem to be bad as far as heat when sitting still either, but the boy put the eyebolts at each compartment door just in case, so you can tie your dogs out right by the door if you feel the need. This really is an excellent trailer for a hunter that goes on long trips, or field trials, especially if you need lots of storage space. I would not have it for sale if money wasn't tight right now; I am sure everyone is feeling the crunch of the economy