Nice choice, that model is the EWG model (Electronic wastegate), so thats already a step up.
Ive been looking a the M135i/235i variants myself, and im very specific in that if im going to be paying for this, ill want to enusre that i get the model with the Professional Nav system (wide Screen display),
Check up the Vin with BMW which im sure you will be doing anyways given your vehicle history of ownership currently.
From what i understand the M135i are pretty solid cars, and great cars to own, if i sold my E92 335i DCT, thats what id be going for.