MINI Countryman - when should I change the timing chain?

I own a 2013 MINI Countryman SD. When does the cam belt/chain need changing? I also want to have a navigation device retro fitted. What will this cost?
An SD has the 2.0 litre N47 engine and this needs checking regularly for wear in the timing chain plastic tensioner. Possibly a bit easier to get to in a MINI than in a 3 Series because the engine is transverse and it doesn't matter so much that the timing chain is at the back of the engine.

Can't help with retrofit satnav because the installation the the MINI is very specific using the big centre dial. Better simply to get a TomTom or a Garmin from Halfords for a few hundred quid. Car tested here: www.honestjohn.co.uk/road-tests/mini/mini-clubman-.../
Answered by Honest John on

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