The only problem is will you get an honest answer!! Take someone with you is the best thing if you can.
One I wish id ask is does the fuel gauge work as I ran out of fuel as mine is a bit out (says it has 1/4 of tank but doesnt!)
* When is MOT due?
* Mileage done/KMs done
* WEIGHT - and ask to see if weight ticket or braking test sheet from MOT
*Does Cab tilt?
*Why are they selling?
*Is it coachbuilt or conversion?
*When was it last serviced?
*Do they have receipts for work they've had done?
Engine size most think over 140 best cyl size (6) power steering. unlaydn weight but not sure if most would know, dimentions of horse area? how many do you want to carry?
What did it need for last MOT? any receipts for work done?, when was last service? is it a tilt cab if not how do you get to fuel filters etc.