Class 8 Box Truck that can tow a lot

Class 8 box trucks for towing?
I'm a former tractor trailer driver. I want to get a box truck that has an air compensated latch pintle hitch, a big lift gate, and a ramp. I plan on occasionally towing a converter dolly, and also towing normal bumper ball-coupled and pintle hook trailers as well. So I would also put a 3" receiver on the truck. Where do I find people who are knowledgeable about this rare type of box truck?

Is buying something already in this configuration a pipe dream; will I need to buy a cab and chassis and then install everything together? I have zero experience outfitting vocational trucks. How much should I expect to spend? Over $100,000 new? If used, after I get the cab and chassis in my possession, is all the bits and bobs to be ready-to-tow going to be $30,000 plus? I'm not excited to try to separate good vocational truck outfitters from the many not good outfitters.

Obviously need gladhands, electric connector for semi lights and separate electric connector for electric-trailer-brake-trailers, trailer brake controller. I may also want APU at some point, and maybe even someday down the road add a reefer unit to the box.

I might consider a class 7 truck, but I suspect class 6 may certainly be too small.

Thank you

 

What do I plan on hauling in the straight truck, or what do I plan on hauling for trailer(s)?