http://www.pajero.guru/mitsubishi-pajero-buying-guide/
This helped me weed out a lot of cars. Be very picky, check what work will need to be done at the next few services, as this will help you decide what the car is actually worth. The people who sell these cars in the markets couldn't care less about the car or you. It's your money, so be absolutely fussy with handing it over.
Check everything works inside the car, including the back seats, the spare tyre, basically everything.
The guide above will give you a good idea of how you should check the car. I've walked away after 1 minute with some cars.
Best of luck
Sorry, once you've narrowed it down to one, ask a garage to look through it. They could spot other issues, so you can use it to reduce the price further.