Check the previous MOTs!!! If anything to do with Emissions failing, stay clear! It's an expensive job to fix!!!!!
But, the radio knob thing is always sensitive in every
ibiza and the same with heavy clutch.
Things to look for is rust like what everyone's said above, and if it's a five door check rear windows stay up and don't fall down when slam the rear doors!!!
But also the rear bumper, check it's securely on, as mine wasn't and when I went through a puddle fast it blew it right off! Also check that the thermometer is reading a realistic number and not -40 or just ---c or else it cocks up ur heating/cooling control. Oh, and check drivers seat is sturdy, as when first got mine it was missing a bolt or something which made it wobble!
Oh and if you've not heard our 1.4
ibiza engine's before, don't be put off that it sounds like a diesel, lol, that's just what they do!