Might have found one...need advice

[Stano]

Found a guy selling a 2003 Thomas, 5.9 Cummins, Allison automatic, next to new rear tires and 70% front. He says the motor runs excellent. I only have one pic of it and thinking it is a front engine due to the winter front on the front. He is supposed to send me more and the mileage. I am guessing it is about 33 ft due to it having 11 or 12 windows. Don't have a lot of info about it like how long it has sat, type of Ally tranny, things like that just yet. What I would like to know...from what I have stated, a price to offer him since it is "offers" add.
Just need a little advice since this would be my very first find of what I am sorta looking for and first reply. I understand that I would need to go see it and need more info.