[TW]Fox said:
Because he likes to jump on the bandwagon
The 620Ti is probably the least crap car of them all. It's all Honda, bar the engine which if looked after won't cause you any more trouble than any other engine.
To the OP, you've done well to find one with such low miles. They're nice, comfortable and pretty quick (dare I say it... quite rapid for a family saloon). The only things really to look out for are an oil weep at the corner of the head (just under the exhaust manifold). If one is present, you won't be able to miss it... just a nice build up of oil dirty oil running down the engine.
Being a 98 however, it might have already had the HG swapped for a Klinger gasket which is stronger and doesn't have the same problem as the older gaskets (before anyone says it, it isn't OMGHGF

It's just caused by the oil way at the front of the block wearing away and weeping a bit. The car won't spontaneously combust).
Other things to look out for are noises from the gearbox. With the clutch out and the box in neutral, listen for any whirring. Dip the clutch a few times to see if the noise changes. Take it for a drive, make sure it goes into gear properly (especially reverse) and that there are no grinding noises. There shouldn't be any problems if the car hasn't been tinkered with. It's only if you fit a boost controller where problems arise.
My 111k box was absolutely silent when I got the car. It had done 107k and there wasn't a whine to be heard. Fit a boost controller and 4k later it's whining like my mum on a power trip

Gonna have to get that seen to soon with a gearbox rebuild (replace the bearings which are plastic caged, with some steel caged upgrades).
And of course, with any turbo car, look out for smoke on idle/over-run. From about 5k in any gear, come off the throttle and watch out the back window for any blue smoke. Also, park up and give the car 10 minutes to tick over. If there are any signs of smoke it could be the turbo seals or valve-stem seals that need replacing. Again, unlikely for a car with those sort of miles.