Going to CT from Pup.. Insulation Question

Sold my pop up camper and buying a CT. I'm on a limited budget, and will be spending most of said budget on the base trailer. I will be adding upgrades as time and money permits and will be an ongoing build. I live in Texas and will be camping mostly during warm/hot weather. I am wanting to add a window shaker type unit asap. My pup had a roof mounted ac and worked very well at keeping it cool. Here's my question... How much different is a non-insulated pop up than a non-insulated CT. If I wanted to get camping right away, will I be fighting a losing battle at keeping the trailer cool?