Rubbish, there are very unstressed engines. They are very economic also as upto 30-31mpg can be had.
Check for rust.
Check the once warm/hot the gearbox kickdowns easily. Check the sport mode and it should kick down quicker. Test the triptronic ( faux manual and make sure it goes into each gear). Beeping in reverse is normal they are NOT parking sensors
I cant see which car it is does it have brembos? Check the cd player as it will probably skip. See if it has folding mirrors when locking and tilting mirrors when reversing. The car will most likely be silent but this is the way JDM's came. Roof etc needs to be checked. windows should go up and down fine on passenger and drivers side.
Anything else just let me know