Please help NEWBIE A170CDI elegance auto

[el1980]

Dear all

thank you for accepting me into this forum iam currently looking to buy a a170 cdi elegance auto, on a 52 plate which im going to view this saturday, iam new to the mercedes world ive always wanted one and now is my chance having said that i really dont know what to look out for in regards to faults with this particular model .i have researched the a170cdi auto and all that comes up is major gearbox problems and its kind of putting me off the idea of owning that model , i currently own an alfa romeo selespeed and this has giving me nuffing but trouble in the gearbox dept,and i dont want hte same with the merc.
The a class that im going to view is a170 cdi elegance fully auto with 70k on the clock and is priced at £3500 is this good for the year? or should i be weiry ive been told that the cambelt is chain driven ?and never needs to be changed? any light on this or in general with this model would be appreciated i look forward to hearing your expert opinions
many thanks