thinking of returning to Mercedes

Hi folks, it's been a while since I was on here since selling my c class a couple of years ago.

I'm thinking about rerurning in the next week with 55 plate e220cdi auto.

The car in question has 70k on the clock with full history and only one owner, have spoken on the phone about and it seems genuine enough.

Is there anything I should be looking out for on it that might not be obvious on viewing or driving in a short distance.

Thanks in advance for any advice.