Hi luke. Few pointers for you. 1.check underneath car to see if undersealed. 2.check dip stick and look inside of oilcap for cream colour. Sign of bad head gasket. Very uncommon on evos as head gasket strong.but worth checking. 3any sign of damage ie panels and lights and doors with uneven gaps. 4ask for or do an hpi check.
5any history would be good ie.what bhp.servise.been mapped.who did work on car. 6 ask what fuel been running on.98-99 octane would be good answer. 7check tyres as not cheap 2 replace. 8have good look at exhaust for rust. Anyway dont expect pristine as it is used car with few years on clock! Generally evos are solid.amazing performance car. Don't worry too much if few small imperfections. Good luck .let me know how you get on.
The main thing i would check is the crank,if it's walking you will see it wearing the case away,if you take a large flat headed screwdriver or a small pry bar you can check how much play there is in the crank,other than that get someone to press the clutch down while you looking at the crank pulley and see how much it moves.