OP: Have you checked NADA.com or the Black Book (whichever is the vehicle value 'bible' in your area? With the info you have and if you have a fair interior/exterior assessment, you should get a sense of the vehicle's worth in your neck of the woods, from a dealer retail standpoint at least. I personally wouldn't bother with Kelly Blue Book, as they seem to be to vehicle values what Zillow.com is to real estate......overvalued. An '06 with 195K miles might be viewed as 'high mileage' and impact its value.
Agree with all who suggest spending the money on a good mechanic to go through and assess the truck's mechanical health. And yes, an older truck could nickel dime you on non powertrain stuff........ask me how I know! Happy hunting.
