Motability wise CLA any colour is available except designo mountain grey magno and the sun yellow, all interia are no cost option.
there are no optional extras on the Cla apart from Suspension with Adaptive Damping system and a driving assist pack which is only available on the Premium plus variant.
There is confusion around the fact motability did not allow packs to be added but this is where the likes of the executive, Premium, and premium plus is classed as a pack as with the AClass (they’ve now added these packs on the Aclass within the AP on certain variants) but this is not the case with the CLA as it’s now classed as a model variant. As to if you can add the driving assist that would have to be confirmed with Mercedes/Motability but at £1495 on top of the £3499 I can’t see it being a priority for most.