About two years ago, we ordered a 16' reefer box new from Kidron. It included a lot of extras like 4" of insulation all the way around, eight rows of E-Track, heavy duty floor rings, and more. You can see complete specs on my web site. Click the "Truck Photo and Specs" link in my signature below.
The body cost $18,461.50 installed. To answer questions like you are asking, I asked my sales rep how much the same body would have cost if it was built as a dry box. He ran it through his computer pricing program. An exact, apples-to-apples comparison cannot be done because construction techniques differ between reefer boxes and dry boxes. The dry box price was about $12,000.
In other words, the dry box cost was about 2/3 as much as a similar sized and equipped reefer box.
Kidron makes a good product. Even more important, they service what they sell. We will likely return to Kidron for another reefer body when we build our next truck.
The TVAL-capable reefer cost $21,061.50 installed (underbody mount, split installation). So, in ballpark terms you could say the "R" (reefer) part of our CR-unit added about $27,000 to the cost of the truck ($21,000 for the reefer, plus $6,000 extra for a reefer body instead of a dry box), before taxes and financing charges.