If you buy a newer truck. Possibly double the money for upfront cost. Hopefully less repairs and maintenance, but when they do it costs more. Makes better fuel mileage, save as much as $10-15,000 a year, however emissions problems cost can quickly and easily eat that up. Higher insurance cost on newer truck. Newer trucks can give electrical and emission problems that leave you by the road. Wrecker bills eat up your fuel savings quickly. Older trucks will usually get you to a truck stop at least.
I don’t think you can beat an older pre emissions truck 02 or older. I have figured it many times and keep coming back to buying old truck if its just about money. The new trucks save a lot of money but more down time and much higher repair costs eat that up and the guys running them often don’t do as good as a guy in an older truck.
However, if you can’t turn wrenches and do a lot of your own work I wouldn’t get an old one.