Are these produced by the factory or are they a custom build?

Would anyone build a conversion using one of these as the tractor portion?

Comments?

https://racingjunk.com/post/872828/Schwabe-330-Pete-Conv...0&showSuperSize=true

$72,500.00
This truck has less than 50000 miles and is awsome. Gray leather and woodgrain interior,275hp Cat and 6 speed Allison, 410 rear end, 204" wheelbase. 22.5LP tires All Aluminum Alcoa wheels, Chrome dual stacks,Power door and windows. Rear seats convert to sofabed, Reclining Captain seats, rear heat and A/C. Dual diesel fuel tanks plus extra tank on back for your toys. This truck is easy to drive and a real eye catcher! Price is F.O.B. Seattle