Yeah, as has been mentioned, I'd stay the hell away from anything built within the last 5 years. Emissions have turned the once reliable and fuel efficient diesels into expensive, fuel guzzling, unreliable pieces of *censored*.
My father bought an '09 GMC 2500HD with the Duramax for hauling the 21' Seafox and a 28' fifth-wheel camper. Every single time we tried to go fishing down the Cape, the thing would go into LIMP MODE on the highway, and wouldn't get out of it's own way!! Friggin dangerous, and VERY AGGRAVATING!! There was no way to service the DPF yourself - all completely enclosed and welded to the exhaust pipe. A trip to the dealer cost him $200 every time .... and this happened AT LEAST once a month!!
Finally he got so pissed off he finally took our advice, and brought it to the diesel performance shop. They installed an older OEM exhaust system, and tuned out that stupid assed DPF. Gained 3 mpg, and saved $200 a month at the dealer. NOW ... keep in mind this is an '09 - the new ones are even WORSE!! In addition to that stupid filter, you have a UREA tank, which itself costs $6 a gallon or so. Run out of fluid, and your in limp mode yet again. AND, to top it all off, there is no way to get around any of this crap at the performance place. If you try and tune it out, it won't run.
The new tractors (as in tractor-trailer) will SHUT DOWN and leave you stuck on the side of the highway if you run out of urea!!!
If it were me, I'd get on eBay, or pick a town down south and get their local classifieds. Well worth the fuel and time to buy an older one rust-free down there, and bring it up north. You save on insurance and taxes because of it's age, and just as important, you save your SANITY.
Just my .02 - don't say I didn't warn ya!!