motor kms verification

hey guys im looking for a cheap d16 to replace my blown one atm...ive found this ad on trading post,
before i ring this bloke i wanted to know how i could find out that the kms on the motor is what he is telling me?... thanks

heres the ad
http://www.tradingpost.com.au/Automo...=true&AdOnTop=

thanks

theres no real way, only bet is to get a compression test an leak down test to know that the motor is still on good condition