There is a lovely 35is for sale on the forum but at 70k and £15.5k think hes being pretty optimistic. Seems like hes had almost 0 interest not even a reply. I was interested in an almost identical car with 40k and negotiated to 13.5k about 12 months ago. It also had a couple of issues with a rough idle miss fire with the injectors needing to be sorted. We couldn't get a date that suited both parties and with the issue decided to let it go. I would say that car is probably a decent deal at 13-14k considering the mileage.
There are certainly deals to be had with the market looking to be slumping, with the new model on the horizon there may well be a few more for sale
I saw you were after a Valencia Orange? I think they were only available on the facelift models 2013 onward with the pure traction pack.
https://www.cooperbmw.co.uk/~/media/ac2c5eab7e0248b88b36dff19f35ae4b.pdf/